May 10-20, 1969 - US troops capture Hill 937, a.k.a. Hamburger Hill, after a prolonged battle. Advancing into the A Shau Valley as part of Operation Apache Snow in May 1969, US troops encountered strong resistance from the People's Army of North Vietnam. Occupying Hill 937, the North Vietnamese constructed an elaborate system of bunkers and strong points. Utilizing the thick jungle, they were able to move without being spotted by US aircraft. Encountering PAVN troops on Hill 937, the 3rd Battalion of the 187th Infantry opened the battle. Engaging the enemy, the 3/187 was met with determined fire and was unable to maneuver around the North Vietnamese forces due to the severe terrain. The situation was made worse by when US gunships fired on their position by accident. This friendly fire incident was the first of several that occurred during the battle. On May 13, the 3/187 was reinforced and Hill 937 became the focus of American efforts in the valley. Over the next week, US troops fought a brutal battle up the hill before finally capturing it on May 20. Due to the severity of the fighting, Hill 937 was dubbed "Hamburger Hill." Covered extensively by the press, who questioned its necessity, the battle was the last major American assault of the war.