Hill 55 (also known as Nui Dat Son or Camp Muir) is a hill 16 kilometres (9.9 mi) southwest of Da Nang, Quảng Nam Province, Vietnam. The hill is located 3 kilometres (1.9 mi) northeast of the confluence of the Yen, Ai Nghia, and La Tho Rivers and was a United States Marine Corps base during the Vietnam War.