A bike path is a 10 to 12 foot wide path, usually paved, used for recreational activities. Although called a bike path they tend to be "multiple-use", accommodating pedestrians, inline skaters, bicyclists, and horseback riders. Since gentle grades make optimum biking conditions, many bike paths are built on abandoned railroad grades. This procedure is referred to as "rails to trails".
The longest bike path in the United States is the 225-mile Katy Trail. Built on an abandoned railroad grade, the path stretches from Clinton, MO to St. Charles, MO. Not wanting to be outdone, Nebraska has planned a bike path on the old Cowboy Line, which would extend 321 miles when completed. (Only 47 miles are open to the public currently.) Even more ambitious is the Grand Illinois Trail, which will eventually consist of a 475-mile network of bike paths.
Who has right of way on multiple-use bike paths? According to the International Mountain Biking Association:
A "courtesy triangle" sign depicting the who should yield has been developed, and is being adopted by many bike paths in the United States, such as the Washington & Old Dominion Trail in Virginia.
Motor vehicles are prohibited on bike paths.