World's First Subterranean Farm

Far below London's busy Clapham High Street, an enormous underground garden grows hundreds of thousands of the capital's fresh greens.

Whilst Paris is home to the world's largest urban farm - set on the roof of a six-storey building in the busy and fashionable Marais district of the French capital - and Denmark has built a massive vertical farm in the outskirts of Copenhagen, two London entrepreneurs decided to make use of one of London's eight underground World War Two bomb shelters to grow fresh produce indoors. The facility makes use of what would otherwise be an abandoned space 33m below ground level to bring Londoners fresh greens at record speed.

Using 100 percent renewable energy, Growing Underground grows its produce via hydroponics - a soil-free cultivation technique - as well as LED heating. The project has partnerships with UK supermarket giant Marks & Spencer, Whole Foods and also supplies Michelin starred restaurants with their microgreen salads.

Vertical farming projects, like this one, are set to play a crucial role in multiple ways, not least in expanding food supplies to an ever growing population, harvesting multiple crops each year, removing air-miles (and road-miles), and doing so in a pesticide-free, sustainable way.