The 3rd Marine Division is an infantry division of the United States Marine Corps based at Camp Courtney, Marine Corps Base Camp Smedley D. Butler and Okinawa, Japan.It is one of three active duty divisions in the Marine Corps and together with the 1st Marine Aircraft Wing (1stMAW) and the 3rd Marine Logistics Group (3rd MLG) forms the III Marine Expeditionary Force (III MEF).