Mayan Muons and Unmapped Rooms

[Image: "Guatemala Tikal D8006" by youngrobv].

Easily one of the most interesting things I've read in quite a while is how a team of particle physicists from UT-Austin plan on using repurposed muon detectors to see inside Mayan archaeological ruins.
In the new issue of Archaeology, Samir S. Patel describes how "an almost featureless aluminum cylinder 5 feet in diameter" that spends its time "silently counting cosmic flotsam called muons" – "ghost particles" that ceaselessly rain down from space – will be installed in the jungles of Belize.
There, these machines will map the otherwise unexplored internal spaces of what the scientists call a "jungle-covered mound."
In other words, an ancient building that now appears simply to be part of the natural landscape – a constructed terrain – will be opened up to viewing for the first time since it was reclaimed by rain forest.
It's non-invasive archaeology by way of deep space.

[Images: The muon detector, courtesy of the UT-Austin Maya Muon Group].

From the UT-Austin Maya Muon Group website:

The first major experiment of the Maya Muon Group will bridge the disciplines of physics and archeology. The particle detectors and related systems are designed specifically to explore ruins of a Maya pyramid in collaboration with colleagues at the UT Mesoamerican Archaeological Laboratory. The Maya Muon Group will travel to La Milpa in northwest Belize to make discoveries about “Structure 1” – a jungle-covered mound covering an unexplored Maya ruin.

Pointing out that dense materials block more muons, Patel explains that a muon detector can actually detect rooms, spaces, and caves inside what seems to be solid:

A detector next to a Maya pyramid, for example, will see fewer particles coming from the direction of the structure than from other angles: a muon “shadow.” And if a part of that pyramid is less dense than expected – containing an open space for, say, a royal burial – it will have less of a shadow. Count enough muons that have passed through the pyramid over the course of several months, and they will form an image of its internal structure, just like light makes an image on film. Then combine the images from three or four devices and a 3-D reconstruction of the pyramid’s guts will take shape.

Referring to a muon detector already at work on the campus of UT-Austin, Patel writes: "The detector sees in every direction, so it also records muon shadows from the adjacent university buildings, and can even identify empty corridors. Silently, with little tending, it takes a monumental x-ray of the world around it."
"The resulting image," he adds, "will be almost directly analogous to a medical CAT-scan."

[Image: The muon detector, courtesy of the UT-Austin Maya Muon Group].

Install one of these things in New York City and see what you find: moving blurs of elevators and passing trucks amidst the strange, skeletal frameworks of skyscrapers that stand behind it all in a labyrinthine mesh.

[Image: A diagram of how it all works; from this PDF by Roy Schwitters].

Patel goes on to relate the surreal story of physicist Luis Alvarez, who used muons "to scan the inside of an ancient structure" – in this case, Khafre's pyramid at Giza. "Working with Egyptian scientists in the late 1960s," we read, "he gained access to the Belzoni chamber, a humid vault deep under the pyramid."
Like something out of an H.P. Lovecraft story, "Alvarez's team set up a muon detector called a spark chamber, which included 30 tons of of iron sheeting, in the underground room."
Foreign physicists building iron rooms beneath the pyramids! To search for secret chambers based on the evidence of cosmic particles.

[Image: An illustrated depiction of Luis Alvarez's feat; view larger!].

Indeed, we read:

Suspicion of the research team ran high – here was a group of Americans with high-tech electronics beneath one of Egypt's most cherished monuments. "We had flashing lights behind panels – it looked like a sci-fi thing from Star Trek," says Lauren Yazolino, the engineer who designed the detector's electronics.

Alvarez's iron room beneath the monolithic geometry of the pyramid – it's like a project by Lebbeus Woods, by way of Boullée – apparently took one year to perform its muon-detection work.
One day, then, the team took a long look at the data – wherein Yazolino "spotted an anomaly, a region of the pyramid that stopped fewer muons than expected, suggesting a void."
There were still undiscovered rooms inside the structure.

[Image: Wiring up the muon detector, courtesy of the UT-Austin Maya Muon Group].

Excitingly, when Roy Schwitters sets up his muon detector next to the tree-covered mounds of the Mayan city of La Milpa, he should get his results back in less than six months. Sitting there like a strange battery, the detector's ultra-long-term abstract photography of the jungle hillsides vaguely reminds me of the technically avant-garde photographic work of Aaron Rose.
Rose has pioneered all sorts of strange lenses and unexpected chemical developers as he takes long-term exposures of Manhattan.
New York becomes less a city than a kind of impenetrable wall of built space.

[Images: Four photographs by Aaron Rose. View slightly larger].

Again, then, I'm curious what it'd be like to install one of these muon detectors in Manhattan: the shivering hives of space it might detect, as delivery trucks shake the bridges and elevators move up and down inside distant high-rises. What would someone like Aaron Rose be able to do with a muon detector?
Are muon detectors the future of urban art photography?
Perhaps it could even be a strange new piece of public art: a dozen muon detectors are installed in Union Square for six months. They're behind fences, and look sinister; conspiratorialists leave long comments on architecture blogs suggesting that the muon detectors might not really be what they seem...
But the resulting images, after six months of Manhattan muon detection, are turned over as a gift to the city; they are hung in massive prints inside the Metropolitan Museum of Art, near the Egyptian wing, and Neil deGrasse Tyson delivers the keynote address.
Or perhaps a muon detector could be installed atop London's fourth plinth:

The Fourth Plinth is in the north-west of Trafalgar Square, in central London. Built in 1841, it was originally intended for an equestrian statue but was empty for many years. It is now the location for specially commissioned art works.

For six months, a shadowy muon detector will stand there, above the heads of passing tourists, detecting strange and labyrinthine hollows beneath government buildings where sprawling complexes from WWII spiral out of sight below ground.
Or perhaps muon detectors could even be installed along the European coast to discover things like the buried neolithic village of Skara Brae or those infamous Nazi bunkers "that lay hidden for more than 50 years" before being uncovered by the sea. As the Daily Mail reported earlier this month:

Three Nazi bunkers on a beach have been uncovered by violent storms off the Danish coast, providing a store of material for history buffs and military archaeologists.

The bunkers were found in practically the same condition as they were on the day the last Nazi soldiers left them, down to the tobacco in one trooper's pipe and a half-finished bottle of schnapps.

So what else might be down there under the soil and the sands...?
I'm imagining mobile teams of archaeologists sleeping in unnamed instant cities in the jungles and far deserts of the world, with storms swirling over their heads, running tests on gigantic black cylinders – muon detectors, all – that stand there like Kubrickian monoliths, recording invisible flashes of energy from space to find ancient burial sites and old buildings underground.

[Images: Tikal, photographed by n8agrin: top/bottom].

Perhaps all the forests and deserts of the world should be peppered with muon detectors – revealing archaeological anomalies and unexpected spaces in the ground all around us.
Architecture students could be involved: installing muon detectors outside Dubai high-rises and then competing to see who can most accurately interpret the floorplan data.

[Images: "Sobrevolando Tikal, Guatemala," photographed by Eddie von der Becke].

Till one day, ten years from now, an astronaut crazed with emotional loneliness, riding through space with his muon detector, begins misinterpreting all of the data. He concludes – in a live radio transmission broadcast home to stunned mission control supervisors – that his space station has secret rooms – undiscovered rooms – that keep popping up somehow in the shadows...
More to the point, meanwhile, you can read a few more things about Roy Schwitters over at MSNBC – and, of course, at the UT-Austin Maya Muon Group homepage.

The Milky Way is made up of thousands of "substructures such as streams." These "streams" are really clumps of stars – moving at a shared velocity, in a shared direction – that were "ripped" from other galaxies, "most likely small galaxies that were pulled in to create the Milky Way." Streams at the center of the galaxy are thus the oldest, as "you probably build a galaxy up from the inside out." Indeed, the sky is criss-crossed with rivers that flow from the remains of structures unspooling elsewhere.

The Basement Maze of Leavenworth, Kansas

[Image: The "underground town" beneath Leavenworth, Kansas, courtesy of KCTV].

It was reported last week that an "underground city" had been discovered beneath the streets of Leavenworth, Kansas. "Some Leavenworth residents have been unknowingly walking around above an underground city," we read, "and no one seems to know who created it or why."

Windows, doors and narrow paths beneath a title company at South Fourth and Delaware streets lead to storefronts stretching several city blocks and perhaps beyond.
There are also several vaults around town. Some of have them been used for breweries...
Some speculate the underground town was created in the 1800s and could have been used during slavery or for fugitives.

I have to admit, though, especially after looking at the slideshow, that referring to this alternately as an "underground town" and an "underground city" seems like quite an overstatement of the case; it looks more like a few connected basements at most.
But how are you going to get people's attention if all you've discovered is a few empty rooms beneath Main Street...?

(Thanks, Ian!)

Library of Dust

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

There's a spectacular new book coming out at the end of this summer called Library of Dust, by photographer David Maisel, published by Chronicle Books. I had the intensely exciting – and flattering – opportunity to write one of the book's introductory essays; that essay now re-appears below.
I first learned about Library of Dust when I interviewed Maisel back in 2006 for Archinect. In 1913, Maisel explained, an Oregon state psychiatric institution began to cremate the remains of its unclaimed patients. Their ashes were then stored inside individual copper canisters and moved into a small room, where they were stacked onto pine shelves.
After doing some research into the story, Maisel got in touch with the hospital administrators – the same hospital, it turns out, where they once filmed One Flew Over the Cuckoo's Nest – and he was granted access to the room in which the canisters were stored.

[Image: Abandoned rooms of the hospital. From Library of Dust by David Maisel, published by Chronicle Books].

Over time, however, the canisters have begun to react chemically with the human ashes held inside them; this has thus created mold-like mineral outgrowths on the exterior surfaces of these otherwise gleaming cylinders.
There was a certain urgency to the project, then, as "the span of time that these canisters are going to be in this state is really finite," Maisel explained in the Archinect interview, "and the hospital is concerned that they're now basically corroding."

So when I was there just a few weeks ago, photographing for I think the fourth time, there was a proposal being floated that each canister be put into its own individual plastic bag, and then each bag would go into its own individual black box that's made for containing human ashes. And that would be it.

To me, the arc of the project – if it ends like that, which it seems it probably will – has a certain kind of conceptual logic to it that I appreciate. I appreciate the form and the story of these canisters, that they're literally breaking down further every day, even between my visits to the hospital. My time of doing it, then, is finite as well.

In order to deal with the fragility of the objects, and to respect their funerary origins, Maisel set up a temporary photography studio inside the hospital itself. There, he began photographing the canisters one by one.
He soon realized that they looked almost earthlike, terrestrial: green and blue coastal forms and island landscapes outlined against a black background. But it was all mineralogy: terrains of rare elements self-reacting in the dark.
Maisel's photos have now been collected into a gorgeous, and physically gigantic, book. It's expensive, but well worth checking out.
The following is my own essay for the book; it appears alongside texts by Terry Toedtemeier and Michael Roth.

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

• • •
In Haruki Murakami’s novel Hard-boiled Wonderland and the End of the World, an unnamed man finds himself walking through an unnamed town. Its depopulated spaces are framed most prominently by a Clocktower, a Gate, and an Old Bridge. The nameless man is told almost immediately to visit the town’s central Library – an unspectacular building that “might be a grain warehouse” for all its allure. “What is one meant to feel here?” the man asks himself, crossing a great, empty Plaza. “All is adrift in a vague sense of loss.”

Once inside the Library, the man meets a Librarian. The two of them sit down together, and the man prepares to read dreams. They are not fairy tales written in pen and ink, however, but the psychic residues of long-dead creatures, a gossamer field of electrical energy left behind in the creatures’ bleached skulls. Weathered almost beyond recognition, one such skull is “dry and brittle, as if it had lain in the sun for years.” The skull has been transformed by time into something utterly unlike itself, marked by processes its former inhabitant could not possibly have anticipated.

Each skull is the most minimal of structures, seemingly incapable of bearing the emotions it stores hidden within. One skull in particular “is unnaturally light,” we read, “with almost no material presence. Nor does it offer any image of the species that had breathed within. It is stripped of flesh, warmth, memory.” It is at once organic and mineralogical – living and dead.

The skull is also silent, but this silence “does not reside on the surface, [it] is held like smoke within. It is unfathomable, eternal” – intangible. One might also add invisible. This “smoke” is the imprint of whatever creature once thought and dreamed inside the skull; the skull is an urn, or canister, a portable tomb for the life it once gave shape to.

The Librarian assists our nameless narrator by wiping off a thin layer of dust, and the man’s dream-reading soon begins.


[Images: From Library of Dust by David Maisel, published by Chronicle Books].

Dust is a peculiar substance. Less a material in its own right, with its own characteristics or color, dust is a condition. It is the “result of the divisibility of matter,” Joseph Amato writes in his book Dust: A History of the Small and the Invisible. Dust is a potpourri of ingredients, varied to the point of indefinability. Dust includes “dead insect parts, flakes of human skin, shreds of fabric, and other unpleasing materials,” Amato writes.

Many humans are allergic to dust and spend vast amounts of time and money attempting to rid their homes and possessions of it, yet dust’s everyday conquest of the world’s surfaces never ends. Undefended, a room can quickly be buried in it.

Dust lies, of course, at the very edge of human visibility: it is as small as the unaided eye can see. And dust is not necessarily terrestrial. “Amorphous,” Amato continues, “dust is found within all things, solid, liquid, or vaporous. With the atmosphere, it forms the envelope that mediates the earth’s interaction with the universe.” But dust is found beyond that earthly sphere, in the abiotic vacuum of interstellar space, a freezing void of irradiated particles, where all dust is the ghostly residue of unspooled stars, astronomical structures reduced to mist.

Strangely representational, the chemistry of this stardust can be analyzed for even the vaguest traces of unknown components; these results, in turn, are a gauge for whatever hells of radiation once glowed, when the universe burned with intensities beyond imagining. Those astral pressures left chemical marks, marks which can be found on dust.

Such dust – vague, unspectacular, bleached and weathered by a billion years of drifting – can be read for its astronomical histories.

Dust, in this way, is a library.

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

A geological history of photography remains unwritten. There are, of course, entire libraries full of books about chemistry and its relationship to the photographic process, but what the word chemistry fails to make clear is that these photographic chemicals have a geological origin: they are formed by, in, and because of the earth’s surface.

Resists, stops, acids, metals, fixes – silver-coated copper plates, say, scorched by controlled exposures of light – produce imagery. This is then called photography. Importantly, such deliberate metallurgical burns do not have to represent anything. Photography in its purest, most geological sense is an abstract process, a chemical weathering that potentially never ends. All metal surfaces transformed by the world, in other words, have a literally photographic quality to them. Those transformations may not be controlled, contained, or domesticated, but the result is one and the same.

Photography, in this view, is a base condition of matter.

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

David Maisel’s photographs of nearly 110 funereal copper canisters are a mineralogical delight. Bearded with a frost of subsidiary elements, their surfaces are now layered, phosphorescent, transformed. Unsettled archipelagos of mineral growths bloom like tumors from the sides and bottoms – but is that metal one sees, or some species of fungus? The very nature of these canisters becomes suspect. One is almost reluctantly aware that these colors and stains could be organic – mold, lichen, some yeasty discharge – with all the horror such leaking putrescence would entail. Indeed, the canisters have reacted with the human ashes held within.

Each canister holds the remains of a human being, of course; each canister holds a corpse – reduced to dust, certainly, burnt to handfuls of ash, sharing that cindered condition with much of the star-bleached universe, but still cadaverous, still human. What strange chemistries we see emerging here between man and metal. Because these were people; they had identities and family histories, long before they became nameless patients, encased in metal, catalytic.

In some ways, these canisters serve a double betrayal: a man or woman left alone, in a labyrinth of medication, prey to surveillance and other inhospitable indignities, only then to be wed with metal, robbed of form, fused to a lattice of unliving minerals – anonymous. Do we see in Maisel’s images then – as if staring into unlabeled graves, monolithic and metallized, stacked on shelves in a closet – the tragic howl of reduction to nothingness, people who once loved, and were loved, annihilated?

After all, these ash-filled urns were photographed only because they remain unclaimed; they’ve been excluded from family plots and narratives. A viewer of these images might even be seeing the fate of an unknown relative, eclipsed, denied – treated like so much dust, eventually vanishing into the shells that held them.

It is not a library at all – but a room full of souls no one wanted.

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

Yet perhaps there is something altogether more triumphant at work here, something glorious, even blessed. There is a profoundly emotional aspect of these objects, a physical statement that we, too, will alter, meld with the dust and metal: an efflorescence. This, then, is our family narrative, not one of loss but of reunion.

There is a broader kinship being proclaimed, a more important reclamation occurring: the depths of matter will accept us back. We will be rewelcomed out of living isolation. We are part of these elements, made of the dust that forms structures in space.

Maisel’s photographs therefore capture scenes of fundamental reassurance. The mineralized future of everything now living is our end. Even entombed by metal, foaming in the darkness with uncontrolled growths – there is splendor.

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

To disappear into this metallurgical abyss of reactions – photographic, molecular – isn’t a tragedy, or even cause for alarm. There should be no mourning. Indeed, Maisel’s work reveals an abstract gallery of the worlds we can become. Planetary, framed against the black void of Maisel’s temporary studio, the remnant energies of the long dead have become color, miracles of alteration. There are no graves, the photographs proclaim: only sites of transformation.

That is our final, inhuman release.

[Image: From Library of Dust by David Maisel, published by Chronicle Books].

At the end of winter 2005, David Maisel traveled to a small city in Oregon. There were bridges, plazas, and gates. He was there to locate an old psychiatric hospital – a building now housing violent criminals – because the hospital held something that interested him.

Upon arrival, he met with the head of security, who already knew why Maisel had come. The two of them walked down a nearby corridor, where Maisel was shown what he’d been looking for. It was an isolated room behind a locked door – smaller, less official, than expected.

Within it was the Library of Dust.

• • •
David Maisel's Library of Dust is available both through Chronicle Books and through Amazon.com – though you can also buy a signed copy through photo-eye.
Don't miss my earlier interview with David over at Archinect – and, at some point soon, take a long trip through David's website.

(Thanks to Joseph Antonetti for his help with the images – and to editor Alan Rapp for instigating this book in the first place).

Patent Drawings for Geodesic Structures

I stumbled on Buckminster Fuller's patent drawings for geodesic domes today – so I thought I'd re-post them here.

Where structural innovation and the U.S. government intersect.

Church of God, Inflationist

[Image: An inflatable church on the beaches of Sardinia; via the BBC].

Inflatable infrastructure for churchgoers has arrived on the sandy beaches of Sardinia, as a bouncy chapel has been installed for Christians on holiday. "Using compressed air it takes only five minutes to inflate," the Times reports, and it "comes complete with an altar, an apse and a confessional."
Inflatable mosques and temples will be next. An inflatable sacred grove for druids.

[Image: Via the BBC].

The size of your church is directly affected by how much money you can raise – because the only pumps strong enough to inflate the whole structure cost $50,000 or more. Once you get that far, though, you realize there are still more rooms and radiating chapels to inflate... but it takes an even larger – and far more expensive – air pump.
Yet, even then, you find more – nearly impossible to inflate – rooms hidden away inside the structure.

[Image: Via the BBC].

"Who made this thing?" you ask one day, quietly, not wanting to draw attention to yourself; and you learn that there is a Holy Lab of Consecrated Inflatables housed in an unmarked room in the Vatican attics – attics the size of basketball courts – where priests trained in the art of shaping warm air read apocryphal texts on the breath of God, stitching vast sheets of polyethylene together to form Gothic geometries.
It's rumored that the largest inflatable ever created is being designed by the monks of Mount Athos; it will require a small nuclear power plant to fill properly.
Bombproof churches will be erected throughout Syria in what becomes known as the Inflatable Crusade.
In particularly expensive models, assembled by private firms in the Netherlands, inflatable priests will pop out of hidden compartments in the floor when you twist small valves, triggering a recording of Agnus Dei.
Children clap, endless cupolas unfold into the sky, and the real services of the evening begin.

(Thanks, Nicky!)

Quick List 11

[Image: A sketch by Henry Wood, from The New York Times].

Last week, The New York Times took readers to an isolated house called Clingstone, built by a Philadelphian named J.S. Lovering Wharton on a rock in the waters of Rhode Island.

Working with an artist, William Trost Richards, Mr. Wharton designed a shingle-style house of picture windows, with 23 rooms on three stories radiating off a vast central hall; its plan is less a blueprint than a diagram of arrows indicating sightlines. He built it like a mill, Mr. Wood said, with wide planking, sturdy oak beams, diagonal sheathing and an odd flourish: an interior cladding of shingles...

The process of renovating the house, abandoned since the 1940s, was formidable, and the weather can be rough; we read, for instance, that "untethered doors at Clingstone are quickly smashed by the wind."
"This house is always going to have rough edges,” says current resident Henry Wood, an architect.

[Image: Photos by Erik Jacobs for The New York Times].

The house, an act of near-constant maintenance, is now on its way to being green:

Today, solar panels heat the water, and a wind turbine on the roof generates electricity. Rainwater is collected in a 3,000-gallon cistern, then filtered, treated and pumped through the house for cleaning purposes. (Mr. Wood claims it is safe enough to drink, “but my children don’t trust me so we don’t,” he said.) After years of using an activated seawater system that draws in seawater, then treats and filters the waste before releasing it back into the ocean, Clingstone now has the latest generation of composting toilets.

For the time being, Clingstone is the only structure on the island, watching through picture windows as Atlantic storms roll in.
The slideshow, with images by Erik Jacobs, is worth checking out.

[Image: Note the wind turbine. Photo by Erik Jacobs for The New York Times].

Meanwhile, over at Deputy Dog we were introduced to the rotating architecture of the Villa Girasole, a house in Italy that rotates on massing internal roller bearings and exposed tracks paved into the landscape.

[Images: The Villa Girasole, from Deputy Dog, thanks to a link from Marilyn Terrell].

The house, by engineer Angelo Invernizzi, "last rotated in 2002," we read in Chad Randl's new book Revolving Architecture, where many more photographs of the building appear. Randl writes:

Invernizzi and his design team used the villa project as a laboratory for trying out modern materials, from reinforced concrete to fiber-cement wall boards. In keeping with the project's experimental nature, a considerable amount of adaptation and refinement accompanied construction. On the exterior walls Invernizzi substituted aluminum sheet for the original cement finish when cracks appeared after the first trial rotations. As the foundation settled and the rotating mechanism was tested, small cracks also developed along the interior plaster walls of the moving part. Invernizzi concealed the damage by finishing the walls with a canvas covering...

Randl points out that the "layout and form of the moving section are well suited to rotation." Further, the house's occupants could "control rotation using a panel (with three buttons: forward, backward, and stop) in the foyer of the moving part."
You can read more about the house's "rotational machinery" in Randl's book.
I wonder, though, if an interesting children's novel couldn't someday be written about a family who goes off on holiday for the summer in the mountains of Italy, renting a dust-covered and slightly eccentric old house. The young boy or girl, who is left alone all day, for whatever reason the novelist comes up with, finds a small panel one day in the house's towering attics.
Those strange paths in the garden, you see, aren't just paths, they're tracks – and this house doesn't just rotate it travels large distances...

[Image: An under-detailed simulated glimpse of "subterranean cyclones"].

In any case, in a bit of unrelated news, hurricanes of liquid iron have been raging at the earth's core for more than 300 million years, simulations suggest. These "subterranean cyclones" have been spinning for the most part below Asia, perhaps explaining the core's seismic asymmetry.

[Image: A new Los Angeles park, rendered by EDAW; spotted at Inhabitat].

Earlier this summer, EDAW released images from its intern design program wherein a new park atop a buried freeway for Los Angeles was the featured subject of discussion. Park 101, as they call it, would be the resulting swatch of artificial land created by covering up the 101 Hollywood freeway. EDAW describes its own plan as "a visionary, and realistic, urban design solution to cap... a relatively small area straddling the 101 freeway, situated in an existing maze of roadways." It will be "an iconic urban park in the heart of downtown Los Angeles... re-visioning the existing infrastructure that supports and encircles the core of the city – freeways, channelized rivers, streets, and public transit."
Considering that L.A. needs very seriously to consider pedestrianization plans, at a huge variety of scales across the whole city, this seems like as good a place as any to begin.
In fact, BLDGBLOG here proposes something like a Pasadena-to-Pacific walking trail: a purpose-built pedestrian boulevard – car-free its whole length, except perhaps for access to emergency services – leading from the beaches of Santa Monica all the way to the foothills of Pasadena, via Griffith Park, encompassing de-paved sections of major cross-city thoroughfares.
A north-south axis would be soon to follow – and the whole thing could perhaps then hook up with the Pacific Crest Trail.

[Image: From some things we made together (on the 405 south) by Sean Dockray].

Speaking of L.A., in response to the previous post, artist Sean Dockray sent in these unexplained images, apparently derived from "freeway loop detector data" on the perpetually clogged 405. We've covered Dockray's work before; in this case, Dockray also drops hints about "a radio station that would be nothing but a reading of [traffic] incidents around [Los Angeles] county (w background music)."
So what do these subtly morphing diagrams really mean?

[Image: Gazex, via anti-avalanche technology].

Finally, Pruned was Alps-bound last week with this look at Gazex, an "explosively effective" anti-avalanche technology embedded in the snow-covered mountainsides.
According to the company's own website, "Gazex explodes an oxygen/propane gas mixture in specifically designed exploder tubes located at the top end of risk zones. The exploders are connected to gas storage tanks with capacities high enough to operate for the whole season without re-filling."
The company boasts that it is the "world leader in remote avalanche prevention control systems."
Clearly, though, it would not be hard to re-purpose this technology, installing hundreds – thousands – of these things in the mountains, anticipating warfare... and then hurling avalanches down upon the heads of invading armies.