Killeen–Fort Hood Regional Airport (IATA: GRK, ICAO: KGRK, FAA LID: GRK) is a small military/commercial joint-use airport that operates alongside Robert Gray Army Airfield. The airport is based inside the south end of the Fort Hood Military Reservation (known as West Fort Hood), six nautical miles (7 mi, 11 km) southwest of the central business district of Killeen, Texas, in unincorporated Bell County. The commercial side replaced the old Killeen Municipal Airport (now Skylark Field) in August, 2004 as that airport was unable to expand.