The Battle of Khe Sanh was conducted in the Khe Sanh area of northwestern Quảng Trị Province, Republic of Vietnam, during the Vietnam War. The main US forces defending Khe Sanh Combat Base (KSCB) were two regiments of the United States Marine Corps supported by elements from the United States Army, the United States Air Force (USAF) and the Royal Australian Air Force (RAAF), as well as a small number of Army of the Republic of Vietnam (ARVN) troops. These were pitted against two to three divisional-size elements of the North Vietnamese People's Army of Vietnam (PAVN).