There is a 35 acre, secret subterranean Cold War city (code named Burlington) 100 feet beneath Corsham, in the city of Wiltshire, UK.
Built in the late 50s, this massive city complex (a interactive map here) was designed to safely house up to 4,000 central Government personnel in the event of a nuclear strike.
Located in a former Bath stone quarry the city was to be the site of the UK’s main Emergency Government War Headquarters – the hub of the Country’s alternative seat of power outside London.
Over a kilometer in length, this city has over 60 miles of roads. Blast proof (for weapons of that time) and completely self-sufficient the secret underground site could accommodate up to 4,000 people, in complete isolation from the outside world, for up to three months.
Although never actually used, the New York grid-style city of roads and avenues was equipped with all the facilities needed to survive. From underground hospitals, canteens, kitchens and laundries to storerooms of supplies, accommodation areas and offices.
This underground city was finally decommissioned in December 2004.