In the decisive one-day Battle of A Sầu, US Amry Special Forces lost their camp of the same name in the A Sầu Valley in Thừa Thiên Province. The camp held 17 US Green Berets and just over 400 Army of the Republic of Vietnam (ARVN) soldiers. Due to its location on South Vietnam’s western border with Laos, the camp was integral to US and ARVN forces in the effort of disrupting the North Vietnamese supply lines along the Ho Chi Minh Trail.
Against the 2,000 strong 325 Division of the People’s Army of Vietnam (PAVN), and suffering from a debilitating shortage of ammunition, US and ARVN troops were quickly overrun, forcing them to evacuate the camp on 10 March.
The PAVN transformed A Sầu Valley into a heavily fortified area with bunkers, antiaircraft guns and artillery. US and ARVN forces were never able to re-establish a permanent presence in the valley for the remainder of the war. During the Tết Offensive, the A Sầu Valley provided Communist troops with an important sanctuary from which to launch attacks on South Vietnamese cities and military bases, especially Huế and Phú Bài. Raids were launched into the valley in April 1968 (Operation Delaware), March 1969 (Operation Dewey Canyon) and May 1969 (Operation Apache Snow), immortalised by the carnage of the Battle of Hamburger Hill.