A weird old story I came across in my bookmarks this morning tells a tale of tunnels under the town of Peterborough, England.
[Image: Gates in Holywell, Peterborough; photo by Rowland Hobson, courtesy of Peterborough Today].
The local newspaper, Peterborough Today, refers to a woman described simply as “a grandmother” who claims “that she crawled through a tunnel under Peterborough Cathedral as a schoolgirl.” That experience—organized as a school trip, of all things—was “terrifying”; in fact, it was “so scary that it gave her nightmares for weeks afterwards.”
About 25 of us went down into the tunnel, one at a time; none of the teachers came in. It was pitch black, had a stone floor and was about two feet high and three feet wide. We crawled along on our hands on knees. The girl in front of me stopped and started screaming, she was so scared. The tunnel started in the Cathedral and ended there too; we were down there for what seemed like ages. When I eventually got home I was in tears. Afterwards I had horrible nightmares for weeks about being buried alive underneath the Cathedral.
What’s fascinating about the story, though, is the fact that not everyone even agrees that these tunnels exist. A “city historian” quoted in the same article says that, while “there are small tunnels under the Cathedral,” they are most likely not tunnels at all, but simply “the ruins of foundations from earlier churches on the site, dating from Saxon times.” The girls would thus have been crawling around amongst the foundations of ruined churches, lost buildings that long predated the cathedral above them.
But local legends insist that the tunnels—or, perhaps, just one very large tunnel—might, in fact, be real. To this end, an amateur archaeologist named Jay Beecher, who works in a local bank by day, has “been intrigued by the legend of the tunnel ever since he was a young boy when he was regaled with tales that had been passed down the generations of a mysterious passageway under the city.” This “mysterious passageway under the city” would be nearly 800 years old, by his reckoning, and more than a mile in length. “Medieval monks may have used the tunnel as a safe route to visit a sacred spring at Holywell to bathe in its healing waters,” we read.
Although Beecher has found indications of the tunnel on city maps, not everyone is convinced, claiming the whole thing is just “folklore.” But it is oddly ubiquitous folklore. One former resident of town who contacted the newspaper “claimed that a series of tunnels ran between Peterborough and Thorney via a secret underground chapel.” Another “said that he recalled seeing part of a tunnel in the cellar at a home in Norfolk Street, Peterborough,” as if the tunnel flashes in and out of existence around town, from basement to basement, church cellar to pub storage room, more a portal or instance gate than an actual part of the built environment. And then, of course, there is the surreal childhood memory—or nightmare—recounted by the “grandmother” quoted above who once crawled beneath the town church with 25 of her schoolmates, worried that they’d all be buried alive in the center of town (surely the narrative premise of a childhood anxiety dream if there ever was one).
No word yet if Beecher has found his archaeological evidence, but the fact that this particular spatial feature makes an appearance in the dreams, memories, or confused geographic fantasies of the people who live there—as if their town can only be complete given this subterranean underside, a buried twin lost beneath churches—is in and of itself remarkable.
The last few years have seen the rise of “soft robots,” squirming, biomorphic, and highly flexible little machines that can be used to slip through cracks, infiltrate tight spaces, even explore architectural ruins in the wake of earthquakes and warfare.
But soft robots are also getting closer to becoming what are, in effect, mechanically agile medical devices that can “monitor your insides,” in the words of Sangbae Kim, assistant professor of mechanical engineering at MIT, as reprinted by Popular Science, sneaking around inside your body like an earthworm.
The so-called “meshworm” is exactly that: a robotic “worm” made from layered wire mesh that uses “nickel-titanium alloy for muscles.” The application of a high temperature “shortens the wire, tightens the spring’s coil, and squeezes that body segment.” Thus, “when a segment contracts, the one behind it stretches out, and the robot inches forward. The tendon also has muscles attached so the robot can turn left or right.”
The result is the oddly grotesque and somewhat phallic creeping machine you see in the short video, above. The idea is that this could be used for medical diagnosis or vascular surgery.
However, the architectural or broadly spatial uses of this technology are also worth considering, including the potential for monumentally scaled-up versions of the meshworm, capable of assisting human or material transport through the built environment—a kind of peristaltic package-delivery tube that could replace the much-discussed pneumatic tubes of an earlier urban era. Like something out of a David Cronenberg film, the city would have a kind of giant bowel-infrastructure distributing waste material from point to point.
More interestingly, though, this new class of soft robots and meshworms could quickly assume their roles as architectural explorers in their own right, burrowing through collapsed buildings, passing beneath or around doors, even being taken up by the more ambitious burglars and tactical operations teams of the world.
Or, for example, earlier this month in the cave state of Kentucky, the annual “Cave City Hamfest” explored how to bring radio transmission deep underground. This was “accomplished by placing handheld (relay capable) walkie-talkies or relay boxes along a cave passage.” “After the inital debugging phase, we demonstrated the ability to simply walk the cave, until data was lost and then backing up a few feet for a solid link. Then placing a radio on a convenient rock and continuing.” Taking this as our cue, we could simply wire-up a team of meshworms with radio repeaters and send a small, crawling team of spelunking robots far ahead of us into caves where no human body can fit; they would crawl until they lose a signal, move back a few feet to re-establish a secure feed, and then the next one squirms dutifully forward.
You’ve thus built a mobile, semi-autonomous, deep-earth radio network made from repurposed medical devices—equal parts cave-mapping expedition and subterranean pirate radio station—opening up whole new realms of underground exploration (and tactical media).
[Image: Machines slide beneath the streets, via Crossrail].
The Crossrail tunnels in London—for now, Europe’s largest construction project, scheduled to finish in 2018—continue to take shape, created in a “tunneling marathon under the streets of London” that aims to add 26 new miles of underground track for commuter rail traffic.
It’s London as Laocoön, wrapped in tunnel-boring machines, mechanical snakes that coil through their own hollow nests beneath the city.
[Image: Looking down through shafts into the subcity, via Crossrail].
What interested me the most in all this, however, was simply that fact that the first tunneling machine put to work in this round of excavation is called Phyllis—
—named after Phyllis Pearsall, widely (but incorrectly?) mythologized as the founder of the legendary A-Z book of London street maps.
There’s something very Psychogeography Lite™ in this, weaving your city together from below with a giant machine-needle named after the woman who (supposedly) first walked the streets of the capital, assembling her book of maps, as if the only logical direction to go, once you’ve mapped the surface of your city, is down, passing through those surfaces to explore larger and darker volumes of urban space.
[Image: Cliffs and caves of Nottingham; photo by Nicola Twilley].
For severalyears now, I’ve admired from afar the ambitious laser-scanning subterranean archaeological project of the Nottingham Caves Survey.
Incredibly, there are more than 450 artificial caves excavated from the sandstone beneath the streets and buildings of Nottingham, England—including, legendarily, the old dungeon that once held Robin Hood—and not all of them are known even today, let alone mapped or studied. The city sits atop a labyrinth of human-carved spaces—some of them huge—and it will quite simply never be certain if archaeologists and historians have found them all.
[Images: Laser scans from the Nottingham Caves Survey show Castle Rock and the Mortimer’s Hole tunnel, including, in the bottom image, the Trip to Jerusalem Pub where we met archaeologist David Strange-Walker; images like this imply an exhilarating and almost psychedelic portrait of the city as invisibly connected behind the scenes by an umbilical network of caves and tunnels. Scans courtesy of the Nottingham Caves Survey].
“Even back in Saxon times, Nottingham was known for its caves,” local historian Tony Waltham writes in his helpful guide Sandstone Caves of Nottingham, “though the great majority of those which survive today were cut much more recently.” From malt kilns to pub cellars, “gentlemen’s lounges” to jails, and wells to cisterns, these caves form an almost entirely privately-owned lacework of voids beneath the city.
[Image: Map of only the known caves in Nottingham, and only in Nottingham’s city center; map by Tony Waltham, from Sandstone Caves of Nottingham].
As Waltham explains, “Nottingham has so many caves quite simply because the physical properties of the bedrock sandstone are ideal for its excavation.” The sandstone “is easily excavated with only hand tools, yet will safely stand as an unsupported arch of low profile.”
In a sense, Nottingham is the Cappadocia of the British Isles.
The purpose of the Nottingham Caves Survey, as their website explains, is “to assess the archaeological importance of Nottingham’s caves. Some are currently scheduled monuments and are of great local and national importance. Some are pub cellars and may seem less vital to the history of the City.”
Others, I was soon to learn, have been bricked off, taken apart, filled in, or forgotten.
“All caves that can be physically accessed will be surveyed with a 3D laser scanner,” the Survey adds, “producing a full measured record of the caves in three dimensions. This ‘point cloud’ of millions of individual survey points can be cut and sliced into plans and sections, ‘flown through’ in short videos, and examined in great detail on the web.”
[Video: One of very many laser-scan animations from the Nottingham Caves Survey].
While over in England a few weeks ago, I got in touch with archaeologist David Strange-Walker, the project’s manager, and arranged for a visit up to Nottingham to learn more about the project. Best of all, David very generously organized an entire day’s worth of explorations, going down into many of the city’s underground spaces in person with David himself as our guide. Joining me on the trip north from London was Nicola Twilley of Edible Geography; architect Mark Smout of Smout Allen and co-author of the fantastic Pamphlet Architecture installment, Augmented Landscapes; and Mark’s young son, Ellis.
[Image: Artificially enlarged pores in the sandstone; photo by BLDGBLOG].
We met the very likable and energetic David—who was dressed for a full day of activity, complete with a well-weathered backpack that we’d later learn contained hard hats and floodlights for each of us—outside Nottingham’s Trip to Jerusalem pub.
Rather than kicking off our visit with a pint, however, we simply walked inside to see how the pub had been partially built—that is, expanded through deliberate excavation—into the sandstone cliffside.
The building is thus more like a facade wrapped around and disguising the artificial caves behind it; walking in past the bar, for instance, you soon notice ventilation shafts and strange half-stairways, curved walls and unpredictable acoustics, as the “network of caves” that actually constitutes the pub interior begins to reveal itself.
My mind was already somewhat blown by this, though it was just the barest indication of extraordinary spatial experiences yet to come.
[Image: Examining sandstone with Dr. David Strange-Walker; photo by BLDGBLOG].
Wasting no time, we headed back outside, where afternoon rain showers had begun to blow in, and David introduced us to the sandstone cliff itself, pointing out both natural and artificially enlarged pores pockmarking the outside.
The sandstone formations or “rock units” beneath the city, as Tony Waltham explains, “were formed as flash flood sediments in desert basins during Triassic times, about 240 million years ago, when Britain was part of a hot and dry continental interior close to the equator. Subsequent eons of plate tectonic movements have brought Britain to its present position; and during the same time, the desert sediments have been buried, compressed and cemented to form moderately strong sedimentary rocks.”
The city is thus built atop a kind of frozen Sahara, deep into which we were about to go walking.
[Image: A gate in the cliff; photo by BLDGBLOG].
Outside here in the cliff face, small openings led within to medieval tunnels and stairs—including the infamous Mortimer’s Hole—that themselves curled up to the top of the plateau; doors in the rock further up from the Trip to Jerusalem opened onto what were now private shooting ranges, of all things; and, with a laugh, David pointed out shotcrete cosmetic work that had been applied to the outer stone surface.
[Image: Artificial shotcrete geology; photo by BLDGBLOG].
We headed from there—walking a brisk pace uphill into the town center—with David casually narrating the various basements, cellars, tunnels, and other urban perforations that lay under the buildings around us, as if we were traveling through town with a human x-ray machine for whom the city was an archaeologically rich cobweb of underground loops and dead-ends.
We soon ended up at the old jails of the Galleries of Justice. A well-known tourist destination, complete with costumed re-enactors, the building sits atop several levels of artificial caves that are well worth exploring.
We were joined at this point by the site’s director, who generously took time out of his schedule to lead us down into parts of the underground complex that are not normally open to the general public.
Heading downward—at first by elevator—we eventually unlocked a door, stepped into a tiny room beneath even the jail cells, crouching over so as not to bang our heads on the low ceiling, and we leaned against banded brick pillars that had been added to help support all the architecture groaning above us.
Avoiding each other’s flashlight beams, we listened as our two guides talked about the discovery—and, sadly, the willful reburial—of caves throughout central Nottingham.
[Image: Brick pillars below Nottingham; photo by BLDGBLOG].
We learned, for instance, that, elsewhere in the city, there had once been a vacuum shop with a cave beneath it; if I remember this story correctly, the shop’s owners had the habit of simply discarding broken and unsold vacuum cleaners into the cave, inadvertently creating a kind of museum of obsolete vacuum parts. Discontinued models sat in the darkness—a void full of vacuums—as the shop went out of business.
We heard, as well, about a nearby site where caves had been discovered beneath a bank during a recent process of renovation and expansion—but, fearing discovery of anything that might slow down the bank’s architectural plans, the caves were simply walled up and left unexplored. They’re thus still down there, underneath and behind the bank, their contents unknown, their extent unmapped—a fate, it seems, shared by many of the caves of Nottingham.
Rather than being greeted by the subterranean and historical wonder that such structures deserve—and I would argue that essentially all of subterranean Nottingham should be declared a UNESCO World Heritage Site—the caves are too often treated as little more than annoying construction setbacks or anomalous ground conditions, suitable only for bricking up, filling with concrete, or forgetting. If the public thinks about them at all, in seems, it is only long enough to consider them threats to building safety or negative influences on property value.
[Images: Learning about caves; photos by BLDGBLOG].
In any case, on our way out of the Galleries of Justice, we lifted up a ventilation grill in the floor and looked down into a small vertical shaft, too narrow and contorted even for Ellis to navigate, and we learned that there are urban legends that this particular shaft leads down to a larger room in which Robin Hood himself was once held… But we had only enough time to shine our flashlights down and wonder.
[Images: Ellis Smout looks for Robin Hood below; photos by BLDGBLOG].
From here, we headed over to our final tourist-y site of the day, which is the awesomely surreal City of Caves exhibition, located in Nottingham’s Broad Marsh shopping mall.
You literally take an escalator down into an indoor mall, where, amidst clothing outlets and food courts, there is an otherwise totally mundane sign pointing simply to “Caves.”
If you didn’t know about Nottingham’s extensive sub-city, this would surely be one of the most inexplicable way-finding messages in mall history.
Here, where we picked our copy of Tony Waltham’s Sandstone Caves of Nottingham pamphlet, from which I’ve been quoting, we learned quite a bit more about how the city has grown, how the caves themselves have often been uncovered (for example, during building expansions and renovations), and what role Nottingham’s underground spaces served during the Nazi bombings of WWII.
[Image: Beneath Broad Marsh shopping mall; photo by BLDGBLOG].
The specific underground complex beneath the shopping mall offers an interesting mix of old tanning operations and other semi-industrial, pre-modern work rooms, now overlapping with 20th-century living and basement spaces that were sliced open during the construction of the Broad Marsh mall.
[Images: Cave spaces beneath the Superstudio-like concrete grid of Nottingham’s Broad Marsh shopping Mall].
That these caves were preserved at all is testament to the power of local conservationists, as the historically rich and spatially intricate rooms and corridors would have been gutted and erased entirely during post-War reconstruction without their intervention.
As it now stands, the mall is perched above the caves on concrete pillars, with the effect that curious shoppers can wander down into the caves through an entrance that could just as easily lead to a local branch of Accessorize.
[Image: A well bucket in the caves beneath Broad Marsh; photo by BLDGBLOG].
Again, we were fortunate to be taken down into some off-limits areas, stepping over lights and electric wires and peering ahead into larger rooms not on the tourist route.
[Images: Lines of lights we switched on in one of the off-limits rooms below Broad Marsh; photo by BLDGBLOG].
This included stepping outside at one point to wander through an overgrown alleyway behind the mall. Small openings even back here stretched beneath and seemingly into the backs of shops; one doorway, a short scramble up a hill of weed-covered rubble, appeared to contain a half-collapsed spiral staircase installed inside a brick-lined sandstone opening.
[Image: A doorway to voids behind Broad Marsh Centre; photo by BLDGBLOG].
At this point, we began to joke about the ease with which it seemed you could plan a sort of speleological super-heist, breaking into shops from below, as an entire dimension of the city seemed to lie unwatched and unprotected.
Nottingham, it appeared, is a city of nothing but doors and openings, holes, pores, and connections, complexly layered knots of space coiling beneath one building after another, sometimes cutting all the way down to the water table.
Incredibly, the day only continued to build in interest, reaching near-impossible urban sights, from catacombs in the local graveyard to a mind-bending sand mine that whirled and looped around like smoke rings beneath an otherwise quiet residential neighborhood.
Leaving the mall behind, and maintaining a brisk pace, David took us further into the city, where our next stop was the Old Angel Inn, another pub with an extensive cellar of caves, in this case accessed through a deceptively workaday door next to an arcade game.
[Images: The Old Angel Inn (top), including the door inside the pub that leads down to the caves below; photos by Nicola Twilley].
Once again, it can hardly be exaggerated how easy it would be to visit or even live in Nottingham and have absolutely no idea that underground spaces such as this can be found almost anywhere. As Tony Waltham points out, “It would be a fair assumption that every building or site within the old city limits either has or had some form of cave beneath it. About 500 caves are now known, and this may be only half the total number that have been excavated under Nottingham.”
In any case, “Although the Old Angel is a ‘modern’ brick building,” as the Nottingham Caves Survey describes the pub on its website, “an investigation of the caves below reveals stone walls belonging to an earlier incarnation. It is likely that there were buildings on this site as far back as the Anglo-Saxon period. Whether the caves beneath are also this old cannot be demonstrated definitively.”
Typical, as well, for these types of pub caves, we found ventilation and delivery tunnels leading back up to the surface, and the walls themselves are lined with long benches, perfect for sitting below ground and, provided you have candles or a flashlight along with you, enjoying a smoke and a pint of beer. As Tony Waltham explains, pub cellars often include “perimeter thralls,” or “low ledges cut in the rock,” normally used for storing kegs and barrels of beer but quite easily repurposed for a quick sit-down.
But I sense I’m going on way too long about all this, especially because the two most memorable details of the entire day were yet to come.
Jumping forward a bit, we left the Old Angel and followed some twists and turns in the street to find ourselves standing outside a nightclub called Propaganda.
Here, David revealed that he has been working on what, in my opinion, will easily be one of the must-have apps of the year. In a nutshell, David has managed to make the subterranean 3D laser-scans of the Nottingham Caves Survey accessible by location, such that, holding up his iPod Touch, he demonstrated that you could, in effect, scan the courtyard we were standing in to see the caves, tunnels, stairways, cellars, vents, storage rooms, and more that lay hidden in the ground around us.
[Images: We test-drive the cave-spotting app; bottom photo by Nicola Twilley].
Ideally, once the Survey’s extensive catalog of 3D visualizations and laser point-clouds has been made available and the app is ready for public download, you will be able to walk through the city of Nottingham, smartphone in hand, revealing in all of their serpentine complexity the underground spaces of the city core.
For anyone who has ever dreamt of putting on x-ray glasses and using them to explore architectural space, this app promises to be a thrilling and vertiginous way to experience exactly that—peering right through the city to see its most ancient foundations.
[Video: A fly-through of the Propaganda Nightclub malting caves].
I, for one, can’t wait to see what David and the Nottingham Caves Survey do with the finished application and I eagerly await its public availability.
[Image: Mark Smout looks for caves in the sky; photo by Nicola Twilley].
I’ll wind up this already quite long post with just a few more highlights.
Nottingham’s Rock Cemetery, north from the center of town along the Mansfield Road, contains, among other things, the collapsed remains of a sand mine. Three of the mine’s old entrances are now gated alcoves surrounded by graves, like something out of Dante. They “are the only surviving remnants of the mine,” Waltham writes in his pamphlet.
[Images: Nottingham’s Rock Cemetery, where archaeologist David Strange-Walker explained the history of the local landscape].
However, an ambitious plan to carve sizable catacombs, inspired by Paris and Rome, through the sandstone beds of the ancient desert here resulted in the never-completed Catacomb Caves, “probably done in 1859-63,” Waltham suggests. These long arched tunnels, accessible through one of the gates described above, eventually lead to a radial terminus from which branch the unused proto-catacombs.
The air there is cloudy with sand—leading me, several days later, to experience a brief attack of hypochondria, worried about developing silicosis—the walls are graffiti’d, and years of trash are piled on the sides of the sandy floor (which has since taken on the characteristics of a dune sea in places, as 150 years of footfall and a collapsing ceiling have led to the appearance of drifts).
[Images: The Rock Cemetery catacomb gates].
What was so extraordinary here, among many other things, was that, for most of this walk through the catacombs, we were actually walking below the graves, meaning that people were buried above us in the earth. At the risk of overdoing it, this felt not unlike becoming aware of an altogether different type of constellation, with bodies and all the stories their lives could tell held above us in a terrestrial sky like legends and heroes, like Orion and Cassiopeia, as we looked up at the vaulted ceiling, flashlights in hand.
[Image: A door on the street—the black door with bars—leading down into a sand mine; photo by BLDGBLOG].
Serving as something of the ultimate proof that Nottingham is a city of overlooked doors that lead into the underworld, there were two locked doors—one of which (the black door, near the sidewalk) appears in the photo, above, another of which, on a street nearby, leads down into the Peel Street Caves—simply sitting there on the sidewalk that, if opened, will take you down into extensive and now defunct sand mines. David’s laser-scans of these for the Nottingham Caves Survey are absolutely gorgeous, as you can see, below.
For a variety of reasons, I am going to avoid being too specific about some of the details here, but, aside from that, I can only enthuse about the experience of donning our hard hats and heading down several flights of comparatively new concrete steps into a coiling and vast artificial cavern from the 19th century, one we spent nearly an hour exploring.
[Image: Nicola Twilley and Mark Smout head down into the sand mine; photo by BLDGBLOG].
Getting lost down there would be so absurdly easy that it is frightening even to contemplate, and, in case the group of us somehow got split up or our batteries ran out of juice, we joked about—if only we could remember them—the easy techniques for navigating a labyrinth offered in Umberto Eco’s novel The Name of the Rose.
[Image: Many of these way-finding signs are actually incorrect, David explained, and seem to have been painted as a kind of sick joke by someone several years ago; photos by BLDGBLOG].
Avoiding such a fate, however, we found graffiti and men’s and women’s latrines; we popped our heads through holes allowing glimpse of other levels; and we cracked our helmets loudly against the low and rough roof more times than I could count.
[Images: Inside the sand mine; all photos by Nicola Twilley].
And even that doesn’t complete the day. From here, heading back out onto the street through a nondescript steel door, as if we had been doing nothing more than watching football in someone’s basement, we went on to eat pie and chips in a restaurant built partially into a cave; we walked back across town, returning to where we started, talking about the future and seemingly obvious possibility of Nottingham’s caves being declared a UNESCO World Heritage Site and thus saved from their all but inevitable destruction (it’s easy to imagine a future in which a tour like the one David gave us will be impossible for lack of caves to see); and we all said goodbye beneath an evening sky cleared of clouds as a late-day breeze began to cut through town.
[Image: Mark & Ellis Smout explore our final “underground” space of the day, the magnificent Park Tunnel; the banded strata clearly visible in the walls show how the tunnel was carved through the dunes of an ancient desert. Photo by BLDGBLOG].
David proved to be a heroic guide that day. His energy never flagged throughout the tour, and he never once appeared impatient with or exhausted by any of our often ridiculous questions—not to mention our tourists’ insistence on pausing every three or four steps to take photographs—and he remained always willing to stay underground far longer than he had originally planned, all this despite having never met any of us before in person and only communicating with me briefly via a flurry of emails the week before.
Meeting David left me far more convinced than I already was that the Nottingham Caves Survey fully deserves the financial support of individuals and institutions, so that it can complete its ambitious and historically valuable work of cataloging Nottingham’s underground spaces and making that knowledge freely accessible to the general public.
Weirdly, England has within its very heart a region deserving comparison to Turkish Cappadocia—yet very few people even seem to know that this subterranean world exists. There very well could be more than 1,000 artificial caves beneath the city, many of them fantastically elaborate, complete with fine carvings of lions and ornate stairwells, and it is actually somewhat disconcerting to think that people remain so globally unaware of Nottingham’s underground heritage.
With any luck, the work of David Strange-Walker, Trent & Peak Archaeology, and the Nottingham Caves Survey will help bring this extraordinary region of the earth the attention—and, importantly, the focused conservation—it is due.
(For further reading, don’t miss Nicola Twilley’s write-up of the tour on her own blog, Edible Geography; and Tony Waltham’s Sandstone Caves of Nottingham, cited extensively in this post, is worth a read if you can find a copy).
Something I’ve meant to post about for awhile—and that isn’t news at all—is the fact that there is a lost lake in the basement of the Empire State Building. Or a pond, more accurately speaking.
After following a series of links leading off from Steve Duncan’s ongoing exploration of New York’s “lost streams, kills, rivers, brooks, ponds, lakes, burns, brakes, and springs,” I found the fascinating story of Sunfish Pond, a “lovely little body of water” at the corner of what is now 31st Street and Fourth Avenue. “The pond was fed both by springs and by a brook which also carried its overflow down to the East River at Kip’s Bay.”
Interestingly, although the pond proper would miss the foundations of the Empire State Building, its feeder streams nonetheless pose a flood risk to the building: the now-buried waterway “leading from Sunfish Pond still floods the deep basement of the Empire State Building today.”
To a certain extent, this reminds me of a line from the recent book Alphaville: “Heat lightning cackles above the Brooklyn skyline and her message is clear: ‘You may have it paved over, but it’s still a swamp.'” That is, the city can’t escape its hydrology.
But perhaps this makes the Empire State Building as good a place as any for us to test out the possibility of fishing in the basements of Manhattan: break in, air-hammer some holes through the concrete, bust out fishing rods, and spend the night hauling inexplicable marine life out of the deep and gurgling darkness below.
[Image: “Caves for New York” (1942) by Hugh Ferriss].
After writing the previous post—about Hong Kong’s impending infrastructural self-burial in the form of artificial caves beneath the island city—I remembered an image by Hugh Ferriss, preeminent architectural illustrator of the early 20th century, exploring huge air-raid shelters for New York City carved out of the rock cliffs of New Jersey.
“These shelters were to be 30 meters high and 60 meters wide and cut into the cliffs of the Hudson Palisades along the New Jersey side, and were to house planes, factories and hundreds of thousands of people,” Jean-Louis Cohen recounts in the recent book Architecture in Uniform: Designing and Building for the Second World War.
While this, of course, never happened, it’s a heady thing to contemplate: an alternative New York City burrowed deep into the geologic mass of New Jersey, a delirium of excavation heading west, away from these islands at risk from wartime annihilation, in a volumetric Manhattanization of empty bedrock.
Now, according to the South China Morning Post, civil engineers in Hong Kong are exploring the possibility of developing large-scale underground spaces—artificial caves—for incorporation into the city’s existing infrastructure. In the full text of the article, available online courtesy of Karst Worlds, we read that the Hong Kong government “is moving towards burying bits of the city—the unsightly ones—in underground caverns, freeing up more land for housing and economic development.”
This is part of a larger undertaking called the Enhanced Use of Underground Space in Hong Kong initiative, a study, backed by Arup, that “would give the government a basis for policy guidelines to encourage cavern developments for both public and private sectors.” Private-sector caverns beneath the city!
Specifically, city engineers “will begin by identifying suitable rock caverns to house 400 government facilities that can be relocated, notably the not-in-my-backyard utilities disliked by nearby residents.” These include “sewage treatment plants, fuel storage depots, refuse transfer stations and columbariums.” The University of Hong Kong, for instance, recently “hid a saltwater reservoir in an artificial cavern next to its Centenary Campus, in a project that cost HK$500 million”; these are referred to as “water caverns.”
Inspired by the fact that “caverns have been used as wine cellars, data centres and car parks in Finland and other countries,” Hong Kong’s Secretary of Development, Carrie Lam, has “called Hong Kong’s rock formations a ‘unique geological asset‘ and urged the city to take caverns into consideration.”
The awesome scale of some of the proposed excavations can be seen in this animation, where, at roughly the one-minute mark, we dive underground and begin to fly through linked 3D models of future freshwater reservoirs. A related PDF outlines a new landscape category—the Strategic Cavern Area—wherein “a strategic area is defined as being greater than 20 hectares in area and having the ability to accommodate multiple cavern sites.” (The idea that your neighborhood might be declared a Strategic Cavern Area, and thus cleared of its building stock, brings to mind a student project featured on BLDGBLOG last month, the “Lower East Side Quarry” by Rebecca Fode).
Sadly, we missed an opportunity to participate in a Hong Kong-based cave-design contest—its deadline was September 2011—called the “Rock Caverns—Unlimited Creativity” competition: “Competition entrants are required, with their unlimited creativity, to propose ideas related to the potential usage of underground space in Hong Kong.” A detailed design guide, called the Geoguide or Guide to Cavern Engineering, was published, and it remains available in full online.
This booklet is nothing less than a builder’s guide to artificial caves. As Chapter 4 helpfully explains, for instance, “In common with other complex constructions, the design of a large underground space is an iterative process where a series of factors influence the final result,” with prospective cave-designers required to use “numerous iterative loops” to create “a cost-effective cavern installation.” The rest of that chapter goes on to explore cavern cross-sections, layout, shape, rock bolts and pattern bolting, and even intra-cave pillars, all of which should find their way into an architecture school design studio somewhere soon.
In any case, while I feel compelled to point out the obvious—that a high-tech labyrinth of artificial caves dug beneath the rocky hills of an over-urbanized tropical archipelago is an incredible setting for future films, novels, and computer games—I should also mention, more prosaically, that Hong Kong’s impending subterranean expansion will doubtless offer many lessons relevant to cities elsewhere, as public-private underground partnerships increase in both number and frequency, with space-starved global mega-cities turning to partial self-burial as a volumetric infrastructural solution to the lack of available surface area.
[Image: Singapore expands beneath the Pacific Ocean; via the BBC].
Singapore has embarked upon the excavation of an underground oil reserve, expanding the city’s industrial port beneath the floor of the Pacific Ocean. It is “no ordinary construction site,” the BBC tells us, but an elaborate project of engineering and infrastructure currently underway “several hundred feet underground, below the seabed in Singapore.”
There, workers are “laboring around the clock to carve out an enormous network of caverns that will eventually store vast amounts of oil.”
[Images: Singapore expands beneath the Pacific Ocean; via the BBC].
More specifically, “Five oil storage caverns are being dug out under the seabed of Banyan Basin, off Jurong island, a series of mostly-reclaimed islands that house most of Singapore’s petrochemical industry.”
Artificial caverns built offshore from manmade islands?
The terrestrial mechanics of Singapore’s existence are increasingly interesting, if ecologically problematic. As Pruned‘s recent look at the city’s sand-importation economy shows, the island-nation exists through a near-ceaseless act of geological accumulation, piecing itself together and expanding from the inside out using deposits of earth taken from neighboring countries.
Singapore, Pruned writes, “has been reclaiming land from the sea since the mid-1960s, expanding its total land area by nearly 25% as a result. And it’s still growing. With no hinterlands to supply it with natural resources, however, it has to import sand, the primary landfill material. But exactly where, the Singaporean government does not disclose. Its supply lines are not public information.”
Earlier this year, we looked at the idea of forensic geology, whereby even a single piece of sand can be tracked back to its terrestrial origins. As that link explains, the source of electronics-grade silicon is often deliberately occluded from public documents, treated as an industrial trade secret. Here, though, it is not microchips but internationally recognized political territory that is being mined, traded, and assembled—a black economy without audit or receipts.
Singapore’s off-the-books experiment in sovereign expansion—not through military conquest but through intelligent geotextiles, Herculean dredging projects, and, of course, new undersea caverns—is perhaps a kind of limit-case in how nation-states not only utilize natural resources but literally build themselves from the ground up (and down) as political acts of landscape architecture.
For a variety of reasons, I was recently looking at a May 2011 report from the Air Force Research Laboratory on “Robotics: Research and Development.”
[Image: From an Air Force Research Laboratory presentation on “Robotics: Research and Development”].
There—amidst plans for unmanned robotic ground convoys and autonomous perimeter defense systems for future bases and cities, not to mention fleets of robotic bulldozers field-tested for use in mine-clearance operations—there was one slide about something called “counter tunnel robotics.”
Being obsessed with all things underground, this immediately caught my eye—especially as this is a program whose goal is to “develop an unmanned system with the capability to access, traverse, navigate, map, survey, and disrupt operations in rough subterranean environments.” A “miniature mapping payload” is under development, one that will allow for accurate cartographic surveys of complex underground spaces; but, because current methods “will not work in the more challenging (non-planar) tunnel environments,” the Air Force explains, the new focus for R&D “will be on developing 3D mapping techniques using 3D sensors.”
The [Counter Tunnel Robotics] system is an innovative all-terrain mobility platform capable of accessing tunnel systems through a small (8 inch) borehole and traversing adverse tunnel terrain including vertical obstacles up to 2ft in height and chasms up to 2ft in length. The system’s function is to provide a platform capable of carrying a small sensor package while navigating and overcoming terrain obstacles inside the tunnel. Counter tunnel technologies are needed to support intelligence gathering and safety of troops and personnel in unmapped and unknown tunnel environments. The system is the initial step in achieving a fully autonomous counter tunnel system.
A few things worth pointing out here include the mind-boggling image of “a fully autonomous counter tunnel system” operating on its own somewhere inside the earth’s surface, like something out of a Jonathan Lethem novel, surely fueling the imaginations of scifi screenplay writers the world over—a planet infested with artificially intelligent tunneling machines. But it is also worth noting that these systems will very likely not be confined to use on—or in—the earth. In fact, autonomous tunnel-exploration robots will find a very hearty market for themselves exploring caves on the moon, on Mars, on asteroids, and perhaps elsewhere, in a fairly clear-cut example of military research finding a productive home for itself in other contexts.
However, I also want to mention how fascinating it is to see that the Air Force Research Laboratory is involved in this, as it actually penetrates the surface of the earth and is very much a project of the ground. It is a landscape project. But the implication here is that these autonomous spelunking units are perhaps seen as a new type of ordnance—that is, they are intelligent bombs that don’t explode so much as explore. They are artillery and surveillance rolled into one. Imagine a bomb that doesn’t destroy a building: instead, it drops into that building and proceeds to map every room and hallway.
But, much more interestingly, there is perhaps also an indication here that a conceptual revolution is underway within the Air Force, where the earth itself—geological space—is seen as merely a thicker version of the sky. That is, the ground is now seen by Air Force strategists as an abstract, three-dimensional space through which machines can operate, like planes in the sky, navigating past “terrain obstacles” like so much turbulence. In a sense, the inside of the earth becomes ontologically—and, certainly, technically—identical to the atmosphere: it is an undifferentiated space that can be traversed in all directions by the appropriate machinery.
Flying and tunneling thus become elided, revealed as one and the same activity; and the Air Force is understandably now in the business of the underground.
[Image: “A U.S. Air Force F-22A Raptor Stealth Fighter Jet Executes A Maneuver Through A Cloud Of Vapor”—that is, it tunnels through the sky—”At The 42nd Naval Base Ventura County Air Show, April 1, 2007, Point Mugu, State of California, USA”; photo by Technical Sgt. Alex Koenig, United States Air Force; Courtesy of Defense Visual Information and the United States Department of Defense].
That, of course, or it was simply an issue of the wrong office receiving research funds for this, and, next fiscal quarter, the Army dutifully takes over…
There is clearly a machines-and-robots theme on the blog this morning. I was fascinated last week to read that New York will soon have “its own subterranean wonder: a 200-ton mechanical serpent’s head” buried “14 stories beneath the well-tended sidewalks of Park Avenue.” In other words, a “gargantuan drill that has been hollowing out tunnels for a train station under Grand Central Terminal” will soon become a permanent part of the city, locked forever in the region’s bedrock. It will be left underground—”entombed” in the words of Michael Grynbaum, writing for the New York Times— lying “dormant and decayed, within the rocky depths of Midtown Manhattan.”
The machine’s actual burial is like a Rachel Whiteread installation gone wrong: “In an official ceremony this week, the cutter will be sealed off by a concrete wall; the chamber will then be filled with concrete, encasing the cutter in a solid cast, Han Solo-style, so that it can serve as a support structure for the tunnel. A plaque will commemorate the site.”
“It’s like a Jules Verne story,” the head of construction for NY’s Metropolitan Transportation Authority endearingly remarked. And the machine itself is an alien wonder:
A recent visit to the cutter’s future crypt revealed a machine that evokes an alien life form that crashed to earth a millennia ago. Its steel gears, bolts and pistons, already oxidizing, appeared lifeless and fatigued. A wormlike fan, its exhaust pipe disappearing into the cutter’s maw, was still spinning, its drone not unlike a slumbering creature’s breath.
I’m tempted to write a short story about a cult of Aleister Crowley-obsessed tower dwellers on the Lower East Side, in the year 2025 A.D., intent on resurrecting this mechanical worm, like something out of Dune, goading it to re-arise, pharaonic and possessed, into the polluted summer air of the city. Grinding and belching its way to dark triumph amidst the buildings, now shattered, that once weighed it down, it is Gotham’s Conqueror Worm.
[Image: Promotional poster for the otherwise unrelated film Conqueror Worm, aka Witchfinder General].
But that would be to rewrite something that, to some extent, already exists. In Jonathan Lethem’s recent novel Chronic City, a tunneling machine goes “a little out of control” beneath the surface of New York, resurfacing at night to wreak havoc amongst the boroughs. From the book:
“I guess the thing got lonely—” “That’s why it destroys bodegas?” asked Perkus. “At night sometimes it comes up from underneath and sort of, you know, ravages around.” “You can’t stop it?” I asked. “Sure, we could stop it, Chase, it we wanted to. But this city’s been waiting for a Second Avenue subway line for a long time, I’m sure you know. The thing’s mostly doing a good job with the tunnel, so they’ve been stalling, and I guess trying to negotiate to keep it underground. The degree of damage is really exaggerated.”
And soon the machine—known as the “tiger”—is spotted rooting around the city, sliding out of the subterranean topologies it helps create, weaving above and below, an autonomous underground object on the loose.
In any case, the entombed drill will presumably outlast the city it sleeps beneath; indeed, if it is ever seen again, it will be a much more geological resurrection. As Alex Trevi of Pruned suggested over email, the machine will be “left there, perhaps forever, and will only surface when NYC rises up in a new mountain range and starts eroding.”
(Thanks to Jessica Young for the reminder about Lethem’s tiger).
[Image: The Holland Tunnel Land Ventilation Building, courtesy of Wikipedia].
As described in this PDF, Holland Tunnel has four ventilation structures:
The four ventilation buildings (two in New Jersey and two in New York) house a total of 84 fans, of which 42 are blower units, and 42 are exhaust units. They are capable, at full speed, of completely changing the tunnel air every 90 seconds.
David Gissen briefly explores the architecture of NYC tunnel vents in his book Subnature, opening a window onto the architecture of subterranean weather generation, where unseen machines suck whole atmospheres from the depths of the city. Perhaps we’ll even read someday that New York’s ongoing rash of tornadoes includes a few rogue climate systems belched forth from these vent stacks on the autumnal banks of the Hudson (or perhaps not).
[Image: Gates in Holywell, Peterborough; photo by Rowland Hobson, courtesy of Peterborough Today].
[Image: Machines slide beneath the streets, via 
[Image: Looking down through shafts into the subcity, via 
[Image: Phyllis, via 
[Image: Cliffs and caves of Nottingham; photo by 
[Images: Laser scans from the 
[Image: Map of only the known caves in Nottingham, and only in Nottingham’s city center; map by Tony Waltham, from 
[Image: The extraordinary caves at 
[Image: Artificially enlarged pores in the sandstone; photo by BLDGBLOG].
[Image: A laser scan showing the umbilical connection of 
[Image: Examining sandstone with Dr. David Strange-Walker; photo by BLDGBLOG].
[Image: A gate in the cliff; photo by BLDGBLOG].
[Image: Artificial shotcrete geology; photo by BLDGBLOG].
[Image: Scan of the Guildhall caves, courtesy of the 
[Image: Brick pillars below Nottingham; photo by BLDGBLOG].
[Images: Learning about caves; photos by BLDGBLOG].
[Images: Ellis Smout looks for Robin Hood below; photos by BLDGBLOG].
[Image: Caves; photo by 
[Image: Beneath Broad Marsh shopping mall; photo by BLDGBLOG].
[Images: Cave spaces beneath the Superstudio-like concrete grid of Nottingham’s Broad Marsh shopping Mall].
[Image: A well bucket in the caves beneath Broad Marsh; photo by BLDGBLOG].
[Images: Lines of lights we switched on in one of the off-limits rooms below Broad Marsh; photo by BLDGBLOG].
[Image: A doorway to voids behind Broad Marsh Centre; photo by BLDGBLOG].
[Images: The Old Angel Inn (top), including the door inside the pub that leads down to the caves below; photos by 
[Images: The caves of the Old Angel Inn, courtesy of the 
[Images: We test-drive the cave-spotting app; bottom photo by 
[Image: Mark Smout looks for caves in the sky; photo by 
[Images: Nottingham’s Rock Cemetery, where archaeologist David Strange-Walker explained the history of the local landscape].
[Images: The Rock Cemetery catacomb gates].
[Image: Inside the catacombs; photo by 
[Image: A door on the street—the black door with bars—leading down into a sand mine; photo by BLDGBLOG].
[Image: The 
[Image: Nicola Twilley and Mark Smout head down into the sand mine; photo by BLDGBLOG].
[Image: Many of these way-finding signs are actually incorrect, David explained, and seem to have been painted as a kind of sick joke by someone several years ago; photos by BLDGBLOG].
[Images: Inside the sand mine; all photos by 
[Image: Mark & Ellis Smout explore our final “underground” space of the day, the magnificent Park Tunnel; the banded strata clearly visible in the walls show how the tunnel was carved through the dunes of an ancient desert. Photo by BLDGBLOG].
[Image: Sunfish Pond].
[Image: “Caves for New York” (1942) by Hugh Ferriss].
[Image: The 
[Image: From the 
[Image: From the 
[Image: From the 
[Images: From the 
[Image: From the 
[Image: Singapore expands beneath the Pacific Ocean; via the 
[Images: Singapore expands beneath the Pacific Ocean; via the 
[Image: From an Air Force Research Laboratory presentation on “Robotics: Research and Development”].
[Image: “A U.S. Air Force F-22A Raptor Stealth Fighter Jet Executes A Maneuver Through A Cloud Of Vapor”—that is, it tunnels through the sky—”At The 42nd Naval Base Ventura County Air Show, April 1, 2007, Point Mugu, State of California, USA”; photo by Technical Sgt. Alex Koenig, 
[Image: Photo by Brian Harkin for 
[Image: Promotional poster for the otherwise unrelated film 
[Image: The Holland Tunnel Land Ventilation Building, courtesy of 