Washington is still considered the most bicycle-friendly state in the nation by the League of American Bicyclists, while neighboring Idaho is among the also-rans. But Idaho bike riders pedal under a law that bicyclists in Washington and Oregon covet.

It's usually called the Idaho Stop law. Essentially, it means that bike riders can treat stop signs as mere yield signs, and red lights as stop signs.

Vehicle drivers may harrumph when they see Idaho bicyclists pause and then blow through stop signs, but it's perfectly legal. And the concept makes sense, according to practitioners of leg-powered mobility. Getting a bike rolling from a complete stop requires a lot of energy. A physics professor in California found that a cyclist who rolls through a stop sign at 5 miles an hour uses 25 percent less energy to get back to full speed.

A public heath researcher found that in Idaho, injuries from bike accidents dropped after the state relaxed the law in 11982. Idaho, by the way, is ranked only 20th among states for bicycle-friendly laws, while Washington is ranked number 1 and Oregon, not far behind, at number 5.
 
And commuting by bicycle is rapidly increasing in all three states. In Portland Oregon, the percentage of people pedaling to work has jumped to more than 6 percent in the past decade. It's up to 3.7 percent in Boise and 3.4 percent in Seattle. Nationally, bicyclists account for only about one percent of commuters.