Imagining a City Built for Bicycles

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A lot is made, and rightfully so, of the differences between walkable cities and auto-dependent cities, but isn’t there a middle way? Truly walkable cities, like most medieval walled cities and their small town USA descendents, aren’t really cities in the modern context. They can’t accommodate the scale and diversity we now associate with a city. Auto-dependent cities handle scale and diversity just fine, but they disconnect people from the built environment and each other. But what if we built our cities for bicycles? And I don’t mean just built paths for bikes, but actually designed the entire city around bikes as the single mode of non-pedestrian transport. What would that look like? What benefits and drawbacks would this model have?

Despite currently living in a relatively low-density, generally auto-dependent sunbelt town, I’ve mostly given up driving in favor of a single-speed beach cruiser with a plastic basket bungeed to the back. The experience has been wonderful. It has also sparked a lot of questions about the way cities and towns are laid out, how their residents move from place to place, how rights-of-way interact with the environments they cut through or pass by, and what all of this might mean in terms of sustainable settlements. So I’m going to posit some hypotheses and hazard some guesses in a sort of thought experiment.

It seems to me that a city built for bicycles would be roughly circular in form with a radius of approximately three miles. Nearly every point in the city would be reachable from any other point by most casual bicyclists within 30 minutes. This assumes an as-the-crow-flies route would always be available, which it certainly wouldn’t, but let’s start with these numbers for the sake of the experiment. An approximately three mile radius would mean a total area of about 28 square miles.

At a moderately urban density, say 10K/sq.mi. (that of Zurich, Switzerland, or Providence, Rhode Island), we would have a total population of 280K or so. Up the density to 15K/sq.mi., roughly that of Copenhagen, Denmark, or Cambridge, Massachusetts, and we have 420K people within city limits. Expand the size of the city circle to a five mile radius, still quite bikable for the majority of trips, and we now have a population of nearly 1.2 million. With a density equal to that of Brooklyn the population would rise to 2.7 million. In fact, at this point we would have something that, statistically, is a near-doppelganger of Brooklyn. If the density soared all the way to Manhattan levels, the total population of our imaginable, bikable city would touch 5.5 million (or about that of the cities of Vancouver, Seattle, Portland, San Francisco, and Los Angeles combined). The point being, a city built for bicycles need not be a bucolic college town.

Population densities would seem less intense than in many modern cities, because far less of the total land area would be devoted to streets. Blocks would likely be shorter, with more total rights-of-way than auto-centric cities, but with an average width of roughly one-third to one-half (and sometimes much less) that of autoroutes, relatively high population densities could be achieved without excessive building heights. The whole notion of roads would change, as well. With less surface area to pave and lower maintenance costs due to the bike’s minimal impact, permeable pavers would be a feasible option. Many roads could draw inspiration more from wooded paths than the concrete jungle, embedding a vast network of trees and greenspace throughout the urban core, perhaps even including complete ecosystems that connect to larger wildernesses beyond the city limits.

Personal health would be fostered since transportation would also be exercise. Would obesity cease to exist? What impact would the lack of auto-related noise and air pollution have on the psyche and the lungs? What other social changes would a city built for bikes bring about? It seems that socialization and cooperation would both increase relative to auto-centric cities due to the bicycle’s slower speed (easy to chat as one rides), greater maneuverability (easy to stop and interact with others), and lack of isolation from the surrounding environment (one sees more and is seen more by others when all parties are on bicycles).

What about classism and socioeconomic divides? Would these also be lessened? A city built for bikes would be dominated by apartment buildings, not single-family houses, in order to accommodate a necessarily compact form. Buildings would be viewed as belonging to the city and only borrowed by the individual, and ostentatious shows of wealth in the form of houses or estates would be rare, if not impossible. Without houses or cars as conspicuous signs of financial status, would all classes more easily mix? Would the young and the elderly have greater freedom of movement and be better integrated into society as a whole?

And what about crime? Without getaway cars or roads that can handle speeding, and with a compact enough settled area that one can’t simply disappear into the distance, would violent crime diminish? The sort of built environment we are talking about here wouldn’t support Euclidean zoning, and having mixed-uses woven throughout its fabric would enhance community networks and keep eyes (and all the other parts of a person) on the street. Such street activation could be a further crime deterrent.

Mobility and accessibility both become nearly universal in a city built for bicycles. Bicycles cost little to buy, little to maintain, and they can be ridden by nearly everyone. Transit and para-transit options, such as bike taxis, would be cheap enough for cities to provide extensive coverage. Instead of the scarring caused by most autoroutes, a bicycle transportation network could be a large scale design element. It seems to me that a city built for bicycles would be bustling, equitable, healthy, social, energy efficient, safe, and potentially ecologically sustainable. Food could be grown on rooftops and along cycle routes, as well as in an agricultural band outside the city limits, energy could be generated by neighborhood-specific cogeneration plants.

What about cities with hills? Well, admittedly, a city built for bikes would be built on relatively flat ground, but bike routes can be designed to follow topographic lines, and serious hills could be handled by lift systems such as that employed in Trondheim, Norway (okay, the Trampe probably isn’t the answer, but it is a first step). Bad weather? Routes could be designed with ample tree canopy, attachments that provide protection from the elements could be designed, some routes could even be indoor.

What if you need to carry lots of stuff? Delivery bikes, other working bikes, and bike trailers can handle large loads, and a compact urban form makes multiple trips more feasible. What about importing and exporting large quantities of goods? What about retrofitting current cities? What about—okay, okay! I don’t have all the answers, and the ones I’ve posited are guesses. But just thinking about a city built for bicycles gets me excited, and I’m not even one of those lycra-clad speed cyclists that car drivers love to hate.

For the next week I’m going to explore the effect that bikes have had and might have on cities and towns and the people who inhabit them. Hopefully we’ll both learn something…