However, the current tenants Growing Underground are currently offering tours of their extraordinary farm. Yes, farm! The former shelter is now used to grow micro herbs using hydroponics. A visit involves the amazing experience of standing among thousands of tiny plants bathed in pink light while Northern Line trains rumble nearby.
Growing Underground is the world's first underground farm, and focused on sustainability - the lights are low-energy LEDs, for example. They go on at night and off in the day, so that their warmth is emitted when the tunnels are coldest and electricity - from green suppliers - is cheapest. The matting on which the shoots are grown is recycled carpet. And food miles are obviously minimal!
In one tunnel, seeds are sprouted and the finished product is cut, weighed and packed. In another, the sprouted seeds are grown to harvesting size - still tiny, meaning that they have powerful flavours.
Conditions are carefully controlled to ensure a hygienic, nut-free environment. Visitors wear hairnets, coats and wellies, with the 'clean' side of the changing room entrance carefully divided off. That cleanliness and the white-lined tunnels make this visit rather different than a walk around Clapham South.
Another difference is that it has a lift - invaluable for getting produce out. It's also handy if you don't fancy walking up 180 stairs to the exit.
If you'd like to try the produce from London's strangest farm (do - it's delicious), it's on sale in Ocado, Marks and Spencer and Planet Organic. Alternatively, take one of their tours and get the freshest of punnets to take away!