Fort Lyon was a timber and earthwork fortification constructed south of Alexandria, Virginia as part of the defenses of Washington, D.C. during the American Civil War. Built in the weeks following the Union defeat at Bull Run, Fort Lyon was situated on Ballenger's Hill south of Hunting Creek, and Cameron Run (which feeds into it), near Mount Eagle (plantation). From its position on one of the highest points south of Alexandria, the fort overlooked Telegraph Road, the Columbia Turnpike, the Orange and Alexandria Railroad, the Little River Turnpike, and the southern approaches to the city of Alexandria, the largest settlement in Union-occupied Northern Virginia.
At present the Huntington Station of the Washington Metro is located next to Fort Lyon's former hilltop site, which is commemorated by a historical marker at the north end of the station lot off King's Highway. Office buildings and parking garages now dominate the site's once wide-open views east over the Potomac River.Occupation of Arlington
Before the outbreak of the Civil War, Alexandria County (renamed Arlington County in 1920), the northernmost county in Virginia and the closest to Washington, D.C., was a predominantly rural area. Originally part of the District of Columbia, the land now comprising the county was retroceded to Virginia in a July 9, 1846 act of Congress that took effect in 1847. Most of the county is hilly, and at the time, most of the county's population was concentrated in the city of Alexandria, at the far southeastern corner of the county. In 1861, the rest of the county largely consisted of scattered farms, the occasional house, fields for grazing livestock, and Arlington House, owned by Mary Custis, wife of Robert E. Lee.
Following the surrender of Fort Sumter in Charleston, South Carolina, on April 14, 1861, new American president Abraham Lincoln declared that "an insurrection existed," and called for 75,000 troops to be called up to quash the rebellion. The move sparked resentment in many other southern states, which promptly moved to convene discussions of secession. The Virginia State Convention passed "an ordinance of secession" and ordered a May 23 referendum to decide whether or not the state should secede from the Union. The U.S. Army responded by creating the Department of Washington, which united all Union troops in the District of Columbia and Maryland under one command.
Brigadier General J.F.K. Mansfield, commander of the Department of Washington, argued that Northern Virginia should be occupied as soon as possible in order to prevent the possibility of the Confederate Army mounting artillery on the hills of Arlington and shelling government buildings in Washington. He also urged the erection of fortifications on the Virginia side of the Potomac River to protect the southern terminuses of the Chain Bridge, Long Bridge, and Aqueduct Bridge. His superiors approved these recommendations, but decided to wait until after Virginia voted for or against secession.
On May 23, 1861, Virginia voted by a margin of 3 to 1 in favor of leaving the Union. That night, U.S. Army troops began crossing the bridges linking Washington, D.C. to Virginia. The march, which began at 10 p.m. on the night of the 23rd, was described in colorful terms by the New York Herald two days later:
The occupation of Northern Virginia was peaceful, with the sole exception of the town of Alexandria. There, as Colonel Elmer E. Ellsworth, commander of the New York Fire Zouaves (11th New York Volunteer Infantry Regiment), entered a local hotel to remove the Confederate flag flying above it, he was shot and killed by James Jackson, the proprietor. Ellsworth was one of the first men killed in the American Civil War. Throughout the remainder of the war, Alexandria would lean strongly towards the Confederate government, necessitating continued occupation by a Union garrison.Battle of Bull Run
Over the seven weeks that followed the occupation of northern Virginia, forts were constructed along the banks of the Potomac River and at the approaches to each of the three major bridges (Chain Bridge, Long Bridge, and Aqueduct Bridge) connecting Virginia to Washington and Georgetown.
While the Potomac River forts were being built, planning and surveying was ordered for an enormous new ring of forts to protect the city. Unlike the fortifications under construction, the new forts would defend the city in all directions, not just the most direct route through Arlington. In mid-July, this work was interrupted by the First Battle of Bull Run. As the Army of Northeastern Virginia marched south to Manassas, the soldiers previously assigned to construction duties marched instead to battle. In the days that followed the Union defeat at Bull Run, panicked efforts were made to defend Washington from what was perceived as an imminent Confederate attack. The makeshift trenches and earthworks that resulted were largely confined to Arlington and the direct approaches to Washington.
On July 26, 1861, five days after the battle, Maj. Gen. George B. McClellan was named commander of the military district of Washington and the subsequently renamed Army of the Potomac. Upon arriving in Washington, McClellan was appalled by the condition of the city's defenses.
To remedy the situation, one of McClellan's first orders upon taking command was to greatly expand the defenses of Washington. At all points of the compass, forts and entrenchments would be constructed in sufficient strength to defeat any attack. Alexandria, which contained the southern terminus of the Chesapeake and Ohio Canal and one of the largest ports in the Chesapeake Bay, was an object of "anxious study."Planning and construction
Gen. Horatio Wright, who had overseen the construction of Fort Ellsworth, and Gen. John Newton, who was in charge of the forts south of Four Mile Run, supervised the construction and managed the flow of men and material. It had 31 guns, including 4 - 200 pounders, (8 inch Parrott rifle), and 16 mortars, and was surrounded by abatis, and rifle pits. It was named for General Nathaniel Lyon, who was killed at the Battle of Wilson's Creek, Missouri, August 10, 1861.Wartime use
General Samuel P. Heintzelman, was headquartered at Fort Lyon, southwest of Alexandria, when he was in charge of the defense of Washington from 27 October 1862 - 13 October 1863. Robert Knox Sneden served there on his staff, from January 12, 1862 to March 22, 1862, when they embarked for the Peninsula Campaign.
On June 9, 1863, Fort Lyon was rocked by an enormous black powder explosion that resulted in the deaths of 25 soldiers and the destruction of eight tons of powder and several thousand rounds of ammunition. The explosion was loud enough to be heard in nearby Alexandria, and one witness noted:
In the wake of the explosion, Fort Lyon, and Alexandria were visited by many military and civilian dignitaries, including Secretary of War Edwin Stanton and President Abraham Lincoln.
The garrison was originally the 16th New York Volunteer Infantry Regiment, 26th New York Volunteer Infantry Regiment, 27th New York Volunteer Infantry Regiment, 107th New York Volunteer Infantry Regiment, 142nd Ohio Infantry, 15th New York Heavy Artillery Regiment. In October 1864, Company's G, H, K, and M, 1st Wisconsin Heavy Artillery Regiment were assigned to the Fort. They were mustered out on June 26, 1865.