Leesburg is the county seat of Loudoun County, Virginia. It was built in 1740, and it is occupied by some of Virginia’s most famous families, being named for Thomas Lee, ancestor of Robert E. Lee. In the War of 1812, it became the temporary seat of the United States government, and in the Civil War, it changed hands several times.
The town is situated at the base of Catoctin Mountain and adjacent to the Potomac River, 33 miles (53 km) northwest of Washington, D.C., for which it has largely become a commuter suburb. Its population was 42,616, as of the 2010 census. This makes it Virginia's largest incorporated town within a county (rather than being an independent city).
Leesburg is 33 miles (53 km) west-northwest of Washington, D.C. along the base of Catoctin Mountain and adjacent to the Potomac River. Its population according to the 2016 United States Census was 52,607  The town is also the northwestern terminus of the Dulles Greenway, a private toll road that connects to the Dulles Toll Road at Washington Dulles International Airport.
Leesburg, like the rest of Loudoun, has undergone considerable growth and development over the last 30 years, transforming from a small, rural, piedmont town to a suburban bedroom community for commuters to the national capital. Growth in the town and its immediate area to the east (Lansdowne/Ashburn) concentrates along the Dulles Greenway and State Route 7, which roughly parallels the Potomac River between Winchester to the west and Alexandria to the east.