As far as upcycling projects go, it's an ambitious one.
A London architect firm wants to transform the capital's disused Tube tunnels into an underground network of cycling routes.
Gensler has won an award for its enterprising London Underline concept, which aims to ease street-level congestion by sending commuters below ground.
The London Underline project envisages easing this strain by taking advantage of the capital's hidden infrastructure.
The far-reaching project sees commuters entering the tunnels via existing tube stations, with Boris bikes available to hire at the entrance.
Its blueprints go further by creating a vision of a vibrant subterranean space filled with artists, pop-up cafes and exhibitions, amid happy crowds of cyclists and walkers.
The plan suggests initially using tunnels between Green Park and Charing Cross Road and between Holborn and Aldwych, in the heart of London, for the project. But it says there are plenty of other spaces that could be adapted too.
It even throws in an eco-friendly element, by proposing the Underline generate its own electricity using kinetic paving from the friction of walkers and passing bikes.
The idea has been commended for its big-sky thinking with an award for Best Conceptual Project at the London Planning Awards this week.
However it is a very long way off landing a green light for planning permission. In fact, news of has already been greeted with cynicism by some commentators, who argue that it is a completely impractical solution to London's congestion problems, because of short tunnel lengths and the non-cycling bridges that connect relevant tube stations.
There are about 40 abandoned or relocated stations on the Underground network, along its entire 255 miles of trackway.
Many of them are already being used for data storage by big corporate organisations and government agencies.
However, a number of projects have been successful in transforming redundant underground space.
The company Growing Underground (above) hit the headlines last year with its plan to grow fresh herbs and salad leaves in the tunnels below the Northern Line, near Clapham North. The project, which gained support from Michelin-starred chef Michel Roux Jr, is now thriving.
And Basement Galley (below) has done phenomenally well with its series of secret supper clubs hosted in a decommissioned 1967 Victoria Line carriage.
Whether or not this new project becomes a reality remains to be seen but we are certainly enthused by the sheer ambition of the idea.
Take a look at the video below, for more details on this imaginative subterranean concept.
What do you think? Could London's disused Tube tunnels be transformed into a cycling network, with restaurants and event space along the way? Or is it a ludicrous idea? Let us know your thoughts in the comments section below
Words: Anna Brech