|Ho Chi Minh, Vietnam|
Originally dug as a base to organize guerrilla style actions against the French, the tunnels were expanded during the Indochina War to become a huge and ingenious underground network. There are more than 200 km of subterraneous complexes contained storage rooms, kitchens, hospitals, sleeping quarters and even schools. The Cu Chi Tunnels have been widened in places for visitors, however they can still be dark, hot and claustrophobic inside so please bear this in mind if you do not like enclosed spaces. For those who choose to stay above the ground there are plenty of easily accessible rooms and excavated areas to visit.