The Ba Làng An Peninsula (Vietnamese: mũi Ba Làng An, literally "land nose of Three Villages called An") is a peninsula in Vietnam. Ba Làng An is located in Quảng Ngãi Province, northeast of Quảng Ngãi and 32 km south of Chu Lai. The name was often mispronounced as "Ba Tang An" and known as Batangan during the Vietnam War, although Far Eastern Economic Review and other sources continued to refer to the "Ba Lang An peninsula."
The "Three Villages called An" which give the name to the peninsula are Vân An, An Chuẩn, and An Hải. The term "ba làng" is native Vietnamese language for "three villages," while the three villages themselves have the usual Sino-Vietnamese names used by Confucian tax-collectors. The Sino-Vietnamese character "An" means "peace," so the villages are sometimes called "Three Villages of Peace".
During the colonial period the waters off the peninsular were recognised as rich fishing grounds. In Nos richesses coloniales 1900-1905 (1906) the cape was called Cap Batangan in French. A French agricultural review (1935) commented that the land of the peninsula was relatively fertile.
Since 1963 the Vietcong converted the Peninsula into a fortified stronghold. Following the conclusion of Operation Starlite, on 24 August 1965, Marine intelligence concluded that the 1st VC Regiment had withdrawn into the Peninsula. Reconnaissance photos of the Peninsula showed a V of older field fortifications pointing inland with the open end to the sea and a new second V further inland under construction.
The Marines, Army of the Republic of Vietnam and Vietnamese Marines conducted Operation Piranha on the peninsula from 7–10 September 1965. The operation resulted in 178 Vietcong killed and 360 enemy and suspected enemy had been captured. Allied losses were two Marines and five South Vietnamese killed.
The Peninsula later became part of the Tactical Area of Responsibility of the Korean 2nd Marine Brigade in 1966 and then the Americal Division, however despite periodic operations the area remained a Vietcong stronghold.