Air raid shelter

One of the London deep-level shelters, in Belsize Park
Kleines Berlin (transl. Little Berlin) is the complex of underground air-raid tunnels dating to World War II, which still exists in Trieste, Italy

Air raid shelters are structures for the protection of non-combatants as well as combatants against enemy attacks from the air. They are similar to bunkers in many regards, although they are not designed to defend against ground attack (but many have been used as defensive structures in such situations).[citation needed]