The most important factor in determining the prevalence of cycling in a city is, arguably, the presence of safe, high-quality, and effective cycling infrastructure. Cycling infrastructure is a broad term for all roads, signs, stations, and more that cyclists make use of. This could include paths that are shared with pedestrians and motorists, in addition to bike-only paths, bike lanes, bike racks, route signs, and specialized traffic signals. Below are a few resources outlining the specifics of cycling infrastructure; click on the photo to go to the website.
Protected Bike Lanes 101 – People for Bikes
The Bicycle Revolution 