Stockwell Deep Level Air-Raid Shelter

The London deep-level shelters are eight deep-level air-raid shelters that were built under London Underground stations during World War II. Each consists of a pair of parallel tunnels 16 feet 6 inches (5.03 m) in diameter and 12,000 feet (3.7 km or 2.3 miles) long. Each tunnel is subdivided into two decks, and each shelter was designed to hold up to 8,000 people.