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Cities, and people who think about cities, are usually all about place and space.  I’d like to make the case instead that cities and the way we think about them – by which I mean, the everyday activities and movement within cities, more than the physical landscape itself – are really all about time.

First, time defines the urban in contrast to the rural.  This is not to say that rural areas exist outside of time, but that they experience it differently.  Time, in agricultural terms, is cyclical, relying on the predictable recurrence of sunrise and sunset, of spring and summer; action is dictated by the length of day and the growing season.  Unpopulated rural areas, forests and wetlands, adhere even more closely to the natural cycle.  Extraction operations like mining may rely less on that cycle, but only through the benefit of technologies like electricity and industrial machinery.  In popular perception, at least, rural life is slow, unhurried, and “close to nature,” relying on the sun rather than the digital clock to tell the time; urban life, in contrast, is fast-paced, frenetic, and full of impatient crowds, rushing so as not to be late.

Suburbs seem to exist in the middle space between these two ideas – slower and calmer than a bustling downtown, but still tied to time-sensitive activities like the morning commute, the after-school program, and the evening news.  Time is still measured, but much of it by the car’s dashboard clock.

It has been observed that we have built our cities with increments of time:  the “forty-five minute rule” claims that city size has historically been determined by the length that can reasonably be travelled in forty-five minutes.  If on foot, about two to three miles; if in a horse-drawn cart, somewhat longer; if by train or car or motorized bus, longer still.  While this may not hold true in all cases, it seems to make sense:  a person can only spend so much of their waking hours travelling, or else nothing would get done.  City height and density may have been determined in part by construction technology and infrastructure limitations, but its breadth may be most practically determined using travel times, not physical distance.

The importance of time in urban movement – and it seems that urban life is all about moving from one place to another – is most evident in public transit.  We often choose one mode over another based on travel times, even if it puts us a couple blocks out of the way; we may even spend more money on a cab just to save time.  Using NextBus and similar tracking services, we determine our schedule by the number of minutes to arrival, not the length or even number of stops the bus or train has to travel.  Our estimated travel time may make one place seem more accessible than the other, even if they are both exactly one mile away.  We measure our reasonable walking radius by minutes as much as by miles; and even in easily-understood grid cities like (midtown) Manhattan or Chicago, we orient ourselves at least as much to the time spent in transit than to the miles we travel every day.  In more chaotic cities like Boston or Paris, the zig-zag distances we travel are hard to measure, and it’s not really worth doing so anyway.

A good rule of thumb:  most places in Chicago seem to take forty-five minutes to reach; most places in Columbus take ten to twenty.  If the destinations are close, we may take a leisurely walk and allow ourselves extra “cushion” time to leave.  If they are further away, driving time must include a traffic jam and some time to search for parking; if taking public transit, we build in extra time to wait for the bus or train, and even more if a transfer is required.  Unless it’s just up the street, we expect to take some extra time getting there.

Trains are most closely linked to time, and are often disconnected from space.  Consider the origin of standard time itself:  the development of cross-country train networks in the United States created the need for a common understanding of when noon or eight or five actually occurred, rather than each town measuring for itself by solar position alone.  (A plaque near the Chicago Board of Trade building commemorates that city’s part in the “invention” of time.)  Because the train’s route and schedule are already circumscribed, we think little of the actual distance we travel, but conceive of the trip more or less as a straight line from A to B, within a given time frame.

Train schedules and maps exist even further out of real, physical space:  the stylized, rectilinear diagram of the London or New York subways alter the form of the city itself to be more legible as a network of colorful lines; stations that appear relatively far apart may indeed be only a block or two away, as is the case with the Regent’s Park and Great Portland Street Tube stations in London. [walking] [by train].

Furthermore, particularly for commuter rail with few or no connecting stations, the schedule is all we really need.  When will it depart?  When will I arrive?  The intermediate locations, not to mention the actual path of the track, is irrelevant.

Inter-city travel may be more or less time-dependent than intra-city.  While we pay attention to miles on the highway, relying on the odometer and the gas tank to remind us when to stop, when we travel by air, we worry primarily about whether or not we’ll miss our flight.  The actual experience of travel is disconnected from the physical distance:  we arrive in one airport, wait a bit, board the plane, perhaps watch landing and takeoff and catch glimpses of farm fields before ascending above the clouds, then touch down again at an eerily similar airport elsewhere.  Frequent flyer miles remain somewhat arbitrary numbers, points we accumulate over time.

Because movement is such an integral part of urban life, we must inevitably rely on time to determine the rest of our actions.  We generally work for a given number of hours, whether or not we are salaried; we take our children to and from school; we must pay attention to opening and closing times of our stores and restaurants and offices; we make appointments and plans and attend events according to the time we have left.  And, of course, somewhere in the midst of everything we find time to sleep.  We find time, lost time, make time, waste time, need more time or time off.  A city itself may be a place, a location, a location in physical space, but in our everyday conception of the city in which we live, it is really a series of time.


On the way to class this morning, I was thinking about routes (I have a choice of 3 bridges to get to campus, whose convenience vary with destination) and street networks.  One of the things we’ve discussed in class is the Problem Of Congestion – primarily with car traffic, but certainly an issue in other modes as well.

In class last semester, the professor raised an interesting question:  is congestion really a bad thing?  One argument is that congestion is not always negatively correlated with quality of life – Paris is congested, but people seem to like it.  Another is that congestion can serve (to some degree) as a self-regulating mechanism in traffic patterns:  for those who don’t have to, travelling at peak time is a pain and a deterrent, keeping a certain number of cars off the road or people off the sidewalks or passengers off the buses and trains.

As I approached the classroom building, I saw more people travelling along the same route, including many of my classmates, coming from either of the two main routes from west campus to the building.  As we approached a central destination, everyone who had taken various routes from wherever they were, were now converging along the two pathways, simulating a bottleneck into the building.  It wasn’t that more people had suddenly appeared on campus, but that everyone wanted or needed to be in this particular spot.

It made me think that maybe this tolerance of congestion can be taken a step further:  it is not a problem, but an inherent property of our social system.  It manifests in where people want to live, where they want to go, even what they want to buy (why else would popular items sell out when substitutes are available?).  Therefore it cannot be “cured” or prevented or even almost-completely reduced, simply understood and (hopefully) managed.

Congestion, or tendency toward congestion, is a property of both space and time.  Many people tend to want to go to the same places, at more or less the same times, and there are only so many ways to get there.  Even on a perfectly-networked grid system, in which many combinations of route segments are possible, most people would tend to choose particular routes because they are most direct, have the least obstructions, or are easiest to travel along arterial paths.  And neither are all destinations equal – rarely does everyone want to be in the same place at the same time, many people want to be in only a few places.

One could argue that congestion is made worse by our current transportation system, by having one central destination or several destinations which aren’t well connected, or by our weekday, work day schedule in which most people need to travel at the same times.  I think it’s deeper than that, however:  whatever its manifestations in specific travel patterns, it comes down to the simple fact that, as William H. Whyte said, people tend to be near other people.  We tend to want to cluster together; to be in the middle of things; to get to the center as quickly and easily as possible; and to be part of larger social phenomena.  Supposed “solutions” to congestion like flex time, telecommuting, or increased transportation capacity can only go so far to alter a pretty fundamental fact about human behavior.

What I’m saying certainly isn’t new, but it’s a view that seems to be absent- or at least not prominent – in discussions of transportation systems.  Congestion is not a problem to be fixed, but an inherent property of our system called Society.  We should find ways to make it better for everyone, but we can’t simply treat it as a waste.  It is, I would argue, a part of what it means to be a social creature.

P.S. – I had to go for the old dictionary move, as I was curious what the -gest part of congestion is.  According to the OED, the earliest definition of congestion is:

The action of gathering or heaping together in a mass; a crowding together; accumulation (1563).

Only later – fittingly, in the mid-19th century, in the middle of the Industrial Revolution and mass urbanization – did it become:

A crowding together or accumulation which disorganizes regular and healthy activity: congested or overcrowded condition, as of population, traffic, etc (1868).

While the tone of both of these definitions is neutral to negative, rather than positive, both also highlight the social nature of congestion.  Only later did the word come to really imply a problem.