Castle Airport is a public airport in unincorporated Merced County, California, 8 miles northwest of Merced. The airport is operated by the Merced County Department of Commerce, Aviation, and Economic Development. It is owned jointly by the city of Merced, the city of Atwater, and Merced County. The airport was formerly designated as Castle Air Force Base, a United States Air Force Strategic Air Command base which was closed after the end of the Cold War in 1995.