Fort Ethan Allen was an earthwork fortification built in Arlington County, Virginia (then still known as Alexandria County) by the Union Army in 1861 as part of the defense of Washington during the American Civil War. The remains of the fort -- a portion of the earthen walls, now overgrown -- are now part of Fort Ethan Allen Park. The historic fort is listed on the National Register of Historic Places, is a designated as an Historic District by Arlington County, and is included as a site in the Virginia Civil War Trails program. Arlington County is a county located in the U.S. state of Virginia (which calls itself a commonwealth), directly across the Potomac River from Washington, DC. By an act of Congress July 9, 1846, the area south of the Potomac was returned to Virginia effective in 1847 As of 2000... Official language(s) English Capital Richmond Largest city Virginia Beach Area  - Total  - Width  - Length  - % water  - Latitude  - Longitude Ranked 35th 110,862 km² 320 km 690 km 7. ... The 21st Michigan Infantry, a company of Shermans veterans. ... 1861 is a common year starting on Tuesday. ... Nickname: the District Motto: Justitia Omnibus (Justice for All) Official website: http://www. ... Combatants United States of America Confederate States of America Commanders Abraham Lincoln† Ulysses S. Grant Jefferson Davis Robert E. Lee Strength 2,213,363 1,064,200 Casualties KIA: 110,100 Total dead: 359,500 Wounded: 275,200 KIA: 74,500 Total dead: 198,500 Wounded: 137,000+  The American... The National Register of Historic Places is the USAs official list of districts, sites, buildings, structures, and objects worthy of preservation. ...