Fort Hunt, the last federal compound erected to defend the nation's capital, and Liberia, the stately 1825 farmhouse in Manassas used by both Confederate and Union forces during the Civil War, have been named Virginia historic landmarks.

Two mansions, a tavern, Roanoke's turn-of-the century water works and the state's only slave chapel, built in 1835 in Fluvanna County, also were cited by the Virginia Historic Landmarks Commission.

All the building, including the two Northern Virginia landmarks, are being nominated to the National Register of Places.

Liberia, built before Manassas grew up around a railroad junction in the 1850s, is one of a dozen Northern Virginia plantations built by descendants of Virginia's Robert (King) Carter, who patented 90,000 acres in Fairfax, Fauquier and Prince William counties for his heirs.

Built on the Carter family's 1660 Libra Plantation, Liberia became the Confederate headquarters of Gen. P.G.T. Beauregard in June 1861, and was visited by Jefferson Davis the following months. A year later, it changed hands and was the headquarters of Union Gen. Irvin McDonnell, who was visited by Abraham Lincoln and Secretary of War Edwin Stanton.

Liberia also was used as a Civil War hospital and the floors still bear bloodstains from those times, according to the present owners, Mr. and Mrs. I. J. Breeden. The house was the only thing left standing after other Manassas buildings were burned during the war.

The Breedens bought the house and about 1,900 acres in 1947 from descendents of German inventor and brewer Robert Portner. Portner, who had a brewery in Alexandria, bought Liberia from Carter descendents after the Civil War.

Mrs. Breeden said this week she and her husband may sell Liberia, but hope it will be purchased by a historic group that could preserve the farmhouse and open it to the public. The City of Manassas already has expressed interest in the property, she said.

Fort Hunt, a popular picnic area run by the National Park Service, orginally was part of George Washington's River Farm, just north of Mount Vernon. The federal government acquired it in the 1890s as part of its $52 million seacoast defense system that included forts to protect 26 U.S. cities.

Concrete batteries with large 8-inch disappearing "rifles" were constructed at Fort Hunt, which was named after Maj. Gen. Henry J. Hunt, a distinguished artillery officer in the Mexican War. A fire tower and 60-inch search light also were constructed. But the fort was dismantled and declared obsolete during World War I, when it briefly became home to an Army finance school before being transferred in 1932 to the National Park Service.

The Civilian Conservation Corps has camps at Fort Hunt in the early 1930s, while helping construct the George Washington Memorial Parkway. British interest in the CCC brought Sir Anthony Eden to Fort Hunt in 1938, and in 1939 Britain's reigning monarchs, King George VI and Queen Mary, visited the fort in an effort to solidify Anglo-American ties before World War II.

The Army took back Fort Hunt during the war, constructing more than 150 buildings for secret operations that later included interrogation of captured German and Japanese officers, who were kept in a small prison at the west end of the compound. The 1898 concrete batteries were used to store highly inflammable nitrate films for the National Archives. Three years after the end of the war, the 197-acre fort reverted to the Park Service.

Today, all that remains of its military past are a few decaying concrete batteries, an officer's house where a Park Service employe now lives and a cavalry horse barn, which the park Service recently announced it plans to tear down.