Cu Chi district, about 40 km northwest of Ho Chi Minh City, is home to one of the most visited historical sites in Vietnam: an extraordinary network of around 200 km of underground tunnels used by resistance fighters during the American War. The tunnels were begun by the Viet Minh in their fight against the French and were later extended by the Viet Cong, who used them to shelter fighters, store supplies, and stage operations while American forces bombed and defoliated the ground above.
At their most elaborate, the tunnels contained kitchens, hospitals, weapons workshops, meeting rooms, and sleeping quarters — a functioning community beneath the earth. The Cu Chi area was one of the most heavily bombed in the war, and the tunnels were the reason so many fighters survived. American troops who found tunnel entrances sent in volunteers called "tunnel rats" to investigate; few wanted the job.
Two sections of the tunnels are open to visitors — Ben Dinh, closer to the city, and Ben Duoc, more authentic and less crowded. Both have been enlarged to allow foreign-sized visitors to enter. A documentary film and museum explain the history. The site can be visited as a day trip from Ho Chi Minh City.