Loudoun County, Virginia, was destined to be an area of significant military activity during the American Civil War. Located on Virginia's northern frontier, the Potomac River, Loudoun County became a borderland after Virginia's secession from the Union in early 1861. Loudoun County's numerous Potomac bridges, ferries and fords made it an ideal location for the Union and Confederate armies to cross into and out of Virginia. Likewise, the county's several gaps in the Blue Ridge Mountains that connected the Piedmont to the Shenandoah Valley and Winchester were of considerable strategic importance. The opposing armies would traverse the county several times throughout the war leading to several small battles, most notably the Battle of Ball's Bluff. The fertile Loudoun Valley, with its wealth of produce and livestock, was of vital importance to the Confederacy and ideal to provide forage for the Union army. Furthermore, Loudoun County's population was deeply divided over secession, and tensions and hostilities against one-time neighbors added to the death and destruction wrought during the war. Bitter partisan warfare kept hostilities active even when the armies were far from Loudoun County. Because of its importance to the Confederacy and the partisans who inhabited it, the Loudoun Valley was put to the torch in The Burning Raid in 1864. It has been said that no county in Virginia that did not witness a decisive battle suffered more than Loudoun. Background Strategic location Located just west-northwest of Washington, D.C., on the south bank of the Potomac River and at the foot of the Blue Ridge, Loudoun served as a connection between northeastern Virginia and the lower Shenandoah Valley as well as between northern Virginia and central Maryland. It was also seen by the Union as a potential staging point for an attack on Washington by way of the Rockville Pike (present-day Maryland Route 355). Transportation Four principal road systems, passing through three gaps in the Blue Ridge, traversed Loudoun from east to west, connecting the county and its neighbor to the east, Fairfax, with those of Clarke and Frederick counties, as well as with Jefferson County, which became part of West Virginia during the war. Fighting occurred along all of these routes as both armies tried to defend or contest the use of the strategic gaps. Little River Turnpike/Ashby's Gap Turnpike – Ashby's Gap Little River Turnpike/Snickersville Turnpike – Snickers Gap Alexandria Pike/ Leesburg and Snickers Gap Turnpike – Snickers