3rd Assault Amphibian Battalion is one of two active duty assault amphibian battalions in the United States Marine Corps. The battalion is tasked with transporting US Marine forces and their equipment from assault ships to shore, and equipped with the Amphibious Combat Vehicle (ACV), which replaced the Amphibious Assault Vehicle (AAV). The battalion is part of the 1st Marine Division and the I Marine Expeditionary Force. The unit is based in Camp Pendleton in California.