Thick City (or: The Escalator Theorem)

I had heard that Hong Kong was a “vertical” city, that its hilly terrain & vertiginous skyscrapers conspired to erase (or at least conceal) the horizontal extent of the metropolis; that limited land area had driven the agglomeration upward (rather than outward) and even the buses aspired to multiple stories… It’s certainly an appealing image, this bustling center of commerce reaching for the stars.

While the sheer number of high rises cannot be denied, in my experience the city is not defined by its top floors or elevator shafts, but by the first few levels above and below ground, by the complex woven circulation network that occupies this thickened ground plane and allows the city to function.

Unlike any city I’ve visited or studied, life in Hong Kong occurs on multiple levels. Pedestrian overpasses span the roads, connecting to mall entrances at the second or third floor, highways coil upward between towers before shooting off towards the hills, funicular railways and world-record escalators compete for tourists, and metro stations span multiple blocks, defining a new underground geography only tangentially related to the streets above.

Every block is a microcosm of the city, with retail, housing, offices and public spaces packed in a dense volume. Big box stores that would normally require acres of parking, dedicated loading docks, and garish, unavoidable architectural branding have carved spaces for themselves below tower complexes that contain hotels, luxury malls, noodle shops, clinics, and subway stations. I found an IKEA in my basement. Its signage competes with the Starbucks next door.

Hong Kong is a city folded in on itself. Each block connects to every other — by street-level connections, but also by underground passages, skyways, and subway stations that act like portals, transporting travelers at speeds unimaginable in the knotty, optimized inefficiency of the streets above.

Long before Hong Kong had developed to this level of complexity, architect and urbanist Otto Wagner proposed a series of urban improvements for Vienna that foreshadow the complexities of this modern metropolis. A few Secessionist subway stations were built, but it is Wagner’s elaboration of the street that I find most intriguing. Wagner proposed separating automobile and pedestrian traffic onto two levels, allowing urban life to continue more or less as it had pre-industrialization, but inserting a high-speed network for cars below. (c. 1894-1902)

These studies were carried to a logical (yet insane) conclusion by the speed-obsessed Futurists, most notably by Antonio Sant’Elia (who had studied under Wagner in Vienna), in the beautiful renderings of his Citta Nuova series of 1914. Here, highway networks, rail lines, power plants took precedence: pedestrians are nowhere to be found, possibly taking cover in the elevated walkways, or in unseen subterranean passages. Less arresting, but more humane is the work of another Wagner disciple, Josef Plecnik, who put the multi-level city into practice in his hometown of Ljubljana, Slovenia, creating a lovely bi-level waterfront promenade, shielding pedestrians and diners on the lower levels from automobile traffic above (1930s).

As Hong Kong continued to develop, so did architectural theory, and examples of “thick” cities can be found in the work of Le Corbusier (Carpenter Center),  Team X, Archigram, Paul Rudolph, and many others associated with the 60s and 70s Brutalist movement. Though many of these projects were conceptual proposals, and some major built projects were spectacular failures, some small successes kept the idea alive. With population growth and urban density a perennial concern, architects continued to study how “thick cities” could be planned.

[“Future New York” c. 1910, from Delirious New York, credited to R. Rummel]

In Delirious New York (1978) Rem Koolhaas emphasizes the potential of the skyscraper to engender multiple programmatic potentials, existing simultaneously on a single block, through vertical stacking and access by lift. He purposefully denies any possible connection between or across blocks — or even between floors — to make an point: that the development of the elevator and the New York City gridiron have enabled new possibilities for architects, though yet unrealized. In the subsequent 30 years of architectural production, Koolhaas and OMA have explored these possibilities, and though in the book he conceives of each block as a self-contained unit, in practice, he does quite the opposite.

In his Jussieu Library proposal of 1992, Koolhaas cuts and folds the stack of floor plates, allowing distant views across and between levels, and creating a continuous space that spirals up through the stacks, (a concept that would reappear in simplified form in OMA’s Seattle Central Library), a conscious rejection of the “Manhattanism” he had identified in Delirious New York.

The Jussieu Library proposal is intriguing not only for its rejection of typical flat floor plates, but for its lack of a facade. This could be a small section of an endless urban space, a thick city connected by tilted planes and escalators.

In this project, Koolhaas seems to be channeling Paul Virilio, whose function oblique diagram contains a powerful political message: that embedded within the flat floors and vertical walls of traditional architecture are the unchallenged power structures and hierarchies of the status quo. For architecture to be truly revolutionary, these ‘structural’ elements must be rethought. The diagram suggests that the form of architecture and the built environment can encourage or discourage different types of movement, different levels of dependence or independence, and ultimately different political acts.

So, if Koolhaas’ straw-man “Manhattanism” can be subverted and (productively) destroyed, could an examination of the structure of Hong Kong inspire new forms of architecture and urban development?

The difficulty lies in Hong Kong’s complexity. New York, for all its nuances, can still be reduced to a clear, two-dimensional diagram for the purposes of architectural speculation, whereas Hong Kong requires (at least) three dimensions.

If we could take a plaster cast of Hong Kong’s subways, overpasses, and surface roads, we would have something like a 3D Nolli Map, or a Sol LeWitt sculpture, crushed during shipping, but that would still not indicate the complexities of security access, temporal shifts (such as Lan Kwai Fong, a busy street by day, pedestrian nightlife hub by night), or the rapidly changing cityscape that characterizes Hong Kong, China, and much of Asia.

Ultimately, I wonder how the study of this city could be useful for future architectural proposals, or urban-scale schemes. I’ll have to think about it. Until then…….


[More photos from Hong Kong, in my Flickr Set.] [note to readers on Facebook – if the images don’t show, try]


  • guilherme

    great post man! The references you’ve done seem to be really accurate…(as I never been in Hong Kong) never thought that the city had developed so much those “utopian” suspended platforms.
    The modernist separation between pedestrians and traffic was always a polemical challenge. However seems that nowadays, as you said, many more interdisciplinary systems are involved and generated..

    • hey g, hope all is well. thanks for reading! after posting, I was digging through an OMA El Croquis, and I think there’s plenty more to analyze in Koolhaas’ work especially — but still nothing comes close to the built complexity of HK.

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