I’ve surrendered to vanity this last year to exercise for exercise’s sake.  For leg strength, I’ve plied overtly pointless three-mile there-and-back through my suburb that involves hills coming and going.  If I can take these hills without bands forming around my legs or shortness of breath, I can pace myself through anything.  I adopted the glib phrase “Strength is made of a whole lot of weakness” years ago.  I believed it only this year.

The great thing about this route is that I am spectacle to no one.  The streets are lined with ticky-tacky boxes in the suburbs of Virginia.  I’m lucky to see 5 people on this route, walking or in traffic.  This is the nicest bike I’ve ever owned, but it doesn’t mean a thing if I don’t have nicer legs to power it.

A fellow GIS geek at work reminded me of a speedometer app called Strava.  Strava tracks your position while you bike, building a map of where all Strava users go.  The resulting heat map is real data on Bike use on all of the world’s streets, and the app is free.

Strava is geared towards exercise, as its two modes are “Biking” and “Running”.  The point of biking is not just about exercise.  When I biked 25 years ago, I did it for transportation.  In Atlanta, a far more hostile town for biking than even the suburbs of today.  The majority of bike trips are for exercise, but they could be for transportation as well.  All it takes is drivers dedicated enough, routes easy enough, or enough things worth biking to within biking distance.


Bikes started out as luxury force multiplier for walk trips in the 1820s, not as exercise per se.  While they were so expensive then as to be affordable only by the idle rich anyway until the 1890’s so they may as well have been about exercise.  The first bike trails in the 1890s were on the outskirts of town.  many were tollways.  To use the trials, bikers had to pay an annual or monthly fee.  This would get them a tag they could affix to their bike, allowing them to pass freely on the trail.

In 1870, a bicycle cost half an average worker’s salary. In 1915, a car cost half an average worker’s salary. Unattainable luxuries for most in their times, but getting cheaper all along.

The dirt and cobblestone streets of the developed towns were too rough, dirty and crowded to bike. Many of the busiest roads, with the most stuff to get to, also had recessed streetcar tracks down the middle to trap and topple bikers.  Due to the state of roads through the 1800’s, wheels developed to serve the needs of bikers in particular.  There was no other means of transportation that was so personally uncomfortable.  Early bikes used straight wooden spokes on steel-banded wheels, just like wagons, to transmit every rock and bump to the biker’s spine. By 1890, bikes had been made far more more survivable by three things: laced spokes, pneumatic tires, and paved roads.


In 1897, just as biking as becoming comfortable and affordable, America’s wealthy were taking up new toys:  bikes with motorized assist.  Paved roads were as vital to the success of motorized traffic as they were to the success of biking.  Unlike the horse drawn wagon, a bike, car, or truck is driven under its own weight.  This is like the trolley, except bikes and cars can be steered anywhere, and paving is much cheaper than precisely measured rails.  The utility of bikes or cars always depended on how many places they could go.  Specifically, where were the good roads.  This was expensive, as there were about 2 million miles of dirt, gravel, and cobblestone roads in the US at the turn of the 20th century.  It wasn’t until the 1920s that states took up the idea of taxing the consumables of cars themselves to pay for all this.

Which brings up the uncomfortable question: are bikers freeloaders?

Even though gas taxes now pay for only 50% of the cost of the upkeep of our 4.5 million miles of roads, at least the gas tax does help to pay for the roads.  The rest is paid for from the general fund.  Which bikers pay when they pay taxes on everything else.

A bike lane in a road is as simple as a stripe in the road 4 feet form the gutter.  This isn’t as safe as a separated cycle track or shared use path, but it is much cheaper to build and maintain.  As with transit, do you want really nice bike lanes or do you want lots of bike lanes.  Even 4 feet at the edge of the road, protected by a shy line, is better than what I had when I biked 60 miles a week in Atlanta.

The cost of this stripe is 90 thousand per mile.  Cheap, compared to the cost of building a traffic lane of 3 million per mile.  In order to make space for bike lanes keeping that cheap price, traffic lanes must be rest ripe as well.  Narrower.  The predominant lane width in America is 12 feet.  Suitable for driving 70 MPH on a freeway and twice as wide as your car.  With a 10% impact to free flow lane capacity, these lanes can be reduced to 10 feet, gaining you the 8 feet you need  on a four lane road.  Traffic doesn’t run at capacity most of the time anyway, and when it does it is usually congested anyway.  The narrower lanes enforce slower speeds on traffic during the rest of the day.  Slower speeds result in safer traffic, measured in fewer collisions, less severe injuries, and fewer fatalities.  All of these cost money.  Money you can save by narrowing the traffic way with bike lanes.

Unfortunately, we haven’t built roads for the last century to manage for safety or even operations.  We’ve built them to manage congestion in the most congested half hours.  Little wonder that traffic violently and involuntarily kills twice as many Americans as guns.

The next advantage of bikes only comes when they are usable as transportation.  They are only usable as transportation when the bike network is safe enough to use for people who are more into getting places than biking itself.  Half of the traffic trips in the US are under 3 miles, easily navigable on a bike.  Easily navigable, that is, if driving a bike from place to place wasn’t ridiculously dangerous and uncomfortable.  We’ve engineered biking out of American transportation over the last century, in the name of congestion management.  As you know, congestion is a marginal event.  100 cars per hour on a road could be free flowing, but 110 could be congested.  Now what if you enabled people to bike the 50% of trips that were within biking distance?  You just doubled the daily traffic capacity of your road, by halving the number of cars on that road.

The final advantage of bikes also has to do with land use.  For biking to be worthwhile as transportation, there have to be things to bike to, within biking distance.  A place worth biking is more densely developed than a place worth driving.  This is not high density, but much higher that what we have known our entire lives.  Think of the neighborhoods in your town that was built before 1920.  Many of these neighborhoods are the nicest, most desirable and most expensive places to live and work in their cities.

This is partially because they are at the center of town, but mostly because they encourage chance encounters and conversations on streets made lively by proximity.  This bump rate makes these neighborhoods inherently prosperous, and worth investing in.  Bikes don’t cause this, but they can expand the scope and connection of these places from 2/10ths of a square mile walkable to 20 square miles bikable.  These neighborhoods are mostly historic, built before we managed cities for traffic, not people.  We have almost forgotten how to build for people, but the point of bikes is to allow it again.

Bikes can be used as both exercise and transportation, if we allow it.  We stand to gain a lot by doing so.