
One of London's more ambitious proposals, the Norman Foster-designed elevated bike paths would use existing rail routes to shoot cyclists around the congested city. The design would comprise a total of 221km of bike paths on 10 routes, accommodating 12,000 cyclists per hour.

A proposal for a floating bike path that would use London's oldest thoroughfare, the river Thames. The 12km stretch would connect Battersea with the Docklands and slice the cycling time between the two destinations by 30 minutes.

The London Underline concept seeks to transform the city's disused metro tunnels into a network of underground pathways for pedestrians and cyclists. London has 250 miles (400km) of metro tunnels and 18 "ghost" tube stations which are not used.

London is now counting on the bicycle as a true transport solution. The city's mayor Boris Johnson has pushed through a proposal for a 24km segregated bike path that will connect the east and the west of the city by 2016.

The Hovenring in the Netherlands is a suspended bicycle path roundabout near Eindhoven. The city council there decided it wanted a piece of infrastructure that not only separated bikes and traffic, but would become an eye-catching tourist attraction as well.

The bike path that connects the Amsterdam suburbs of Krommenie and Wormerveer last year became the world's first road with embedded solar panels over a 70m stretch. When the path is extended to 100m in 2016, it's hoped it will produce enough electricity to power three households.

The bike path as artwork is gaining in popularity. The kilometer-long "Van Gogh-Roosegaarde" cycle path, in the Netherlands, is inspired by Van Gogh's "Starry Night" and features 50,000 glow-in-the-dark stones, which have been embedded in the ground.

Lyon, France's second city, has its own bike share scheme "Velo'v" to rival the "Velib" system of its big sister Paris. But Paris does not have Lyon's "Le Tube" - a 2km car-free route that doubles as a continuous art installation with projected images.

The Spanish city of San Sebastian has converted a disused railway tunnel into what is claimed to be the world's longest bike commuter tunnel. The tunnel allows for quick access to Bilbao, which was previously separated by steep hills.

The Trampe bicycle lift has been in existence for more than 20 years but was recently rebuilt as the new and improved "CycloCable." Using ski-lift technology, cyclists put their right foot on a traveling plate that tows the rider up a 130 meter hill with a gradient of 1:5.