The Cu Chi tunnels were part of a 125-mile long underground maze where thousands of fighters and villagers hid and fought during the Vietnam War (or the American war as the Vietnamese call it). The Viet Cong built this vast network of tunnels in and around the village of Cu Chi and worked continually over 25 years to expand the multi-level network, which includes mess halls, meeting rooms, an operating theater, a tiny cinema, small factories, and vast ammunition stores. The tunnels allowed the Viet Cong to control large areas near Ho Chi Minh City. Without knowing it, the U.S. built a military base right on top of one tunnel networks, allowing the Viet Cong to emerge at night and kill American soldiers.