Landscape architect Sam Martin proposes Skycycle, a separated, elevated system of bike lanes for London. According to the Daily Mail, he gave up cycling in London because he found it too dangerous.
[Transport London] estimate the number of journeys made by bike will treble to around 1.5 million by 2020. Where are they meant to go? SkyCycle is the next logical step, because you can’t realistically build more cycle lanes on ground level. You have to start knocking down buildings and there will always be the problem of traffic. It will be less safe than it is now and you can’t persuade people to get on bikes as it is even if you keep raising taxes on cars.
At Grist, Sarah Laskow notes that " this could be a big win for bikers, graffiti artists, and people who like to pee on the side of the road," but the idea shouldn't be dismissed so lightly. Not because there is no more room for bike lanes in London, which isn't true, but because these kinds of bike lanes serve a totally different purpose.
We've seen this before on TreeHugger, with Chris Hardwicke's proposal for Velo-City. Chris noted that enclosing the cyclists in tubes created a "dynamic air circulation loop that creates a natural tail-wind for cyclists. The reduction in air resistance increases the efficiency of cycling by about 90%, allowing for speeds up to 40 km/hr." (25mph)
The Velo-City circulation system acts much like a controlled access highway system for bikes, moving cyclists at high speed from neighborhood to neighborhood, at which point you transfer to the local bike lane or road grid. Because it is so efficient, it lets cyclists travel longer distances in less time. Like any highway system eventually does, it would increase the number of bikes on the local roads, not decrease them.
Mayor of London Boris Johnson calls the idea "interesting." It is more than that; it isn't just a separated bikelane, it is an elevated bike highway that would change the way bikes are used the way highways for cars did.
Lloyd Alter on Test of Velo-City