http://www.theguardian.com/cities/bike-blog/2014/mar/04/cycling-cities-search-bike-friendly-metropolis

In Copenhagen, Denmark bicycles are the norm and cars are in the minority,  5.2 bicycles for every car. Bikes are actually often the fastest way to get around.  Increased biking usage could not only reduce air pollution and greenhouse gas emissions, but also lower people’s risk of developing a number of diseases. This article examines the bike friendliness of several cities around the world and also shows the dangers involved in cycling.