A trio of companies and organizations worked to create SkyCycle, a conceptual biking path for London that would keep cyclists safe and relieve congestion on the city's streets. Foster + Partners, Exterior Architecture and Space Syntax envision a series of cycling paths built on top of existing train lines. The idea is that cyclists would be kept off the streets (keeping them safe) and that building on top of existing train lines would save both time (cyclists' time and construction time) and money.
SkyCycle would span some 137 miles and would feature 200 access points. Of the 10 different routes, it is estimated that each one could accommodate an average of 12,000 riders per hour. If the idea is give the okay, it's possible to have SkyCycle fully up and running within 20 years.