Like many rural houses, Mount Air has had a succession of owners and building campaigns. Several maps prepared by George Washington showing his neighbors' properties include this site. The main portion of the present house dates from 1859, when it was rebuilt following a fire, but the east wing may date from ca. 1820. Confederate and Union troops stopped at Mount Air for supplies during the Civil War. Army engineers building a railroad spur to Fort Humphrey (now Fort Belvoir) camped on the Mount Air property in 1918. Today, Mount Air, its outbuildings, and formal gardens remain intact, a unique survivor in eastern Fairfax County of an antebellum plantation with earlier colonial associations.