Named after a county in Virginia, the ship was constructed by National Steel and Shipbuilding Company of San Diego, California.

This made the Newport class the first to depart from the standard LST design that had been developed in early World War II.

The LST carried 1,750 long tons (1,780 t) of diesel fuel for a range of 2,500 nautical miles (4,600 km; 2,900 mi) at the cruising speed of 14 knots (26 km/h; 16 mph).

The ship was also equipped with a bow thruster to allow for better maneuvering near causeways and to hold position while offshore during the unloading of amphibious vehicles.

[3][5] The Newport class were larger and faster than previous LSTs and were able to transport tanks, heavy vehicles and engineer groups and supplies that were too large for helicopters or smaller landing craft to carry.

[1][2] The Newport class has the capacity for 500 long tons (510 t) of vehicles, 19,000 sq ft (1,800 m2) of cargo area and could carry up to 431 troops.

[1][7] The vessels also have davits for four vehicle and personnel landing craft (LCVPs) and could carry four pontoon causeway sections along the sides of the hull.

[6] The LST was ordered as the sixth hull of the third group of the Newport class in Fiscal Year 1967 and a contract was awarded on 15 July 1966.

[10] Fairfax County departed San Diego for the ship's new home port, Little Creek, Virginia via the Panama Canal.

MARG 3-90 was kept in the Mediterranean as a show of force to possible belligerent African nations while the United States was occupied in the Persian Gulf.

MARG 3-90 departed Camp Lejeune, North Carolina on 7 August 1990 with a United States Marine Corps detachment and returned to Little Creek on 5 March 1991.