Củ Chi is a suburban district of Ho Chi Minh City in Vietnam. It is famous for its Củ Chi tunnels, an immense network of underground tunnels, which were constructed during the Second Indochina War (1955-1975). They were employed as camouflaged hiding-spots and ambush locations, as well as communication and supply routes, hospitals, living quarters, food and weapons caches. They were the target of major US military bombing operations such as Operation Crimp (January 1966) and Operation Cedar Falls (January 1967). They also served as one of the headquarters for Việt Cộng and National Liberation Front (NLF) guerrillas, used as a major base of operations for the Tết Offensive in 1968.
