Potomac Canal Historic District

Within Great Falls Park in Fairfax County, Virginia, lie the remains of a canal built to carry boats around the Great Falls of the Potomac. The Patowmack Canal Company worked on it from 1785 to 1802. The route runs about three-quarters of a mile and once had a wing dam, guard gates, a two-acre holding basin and five locks. The lowest locks were blasted from solid rock with black powder in hand-drilled holes. The canal was part of a plan, backed by George Washington, to make the Potomac navigable toward the Ohio country, and Maryland and Virginia bought nearly half the company's shares. The company failed financially and dissolved in 1826. Nearby ruins include the planned town of Matildaville, founded by Henry Lee, along with mill and foundry sites, a log inn and a superintendent's house. Today the canal is a ruin, but it preserves significant evidence of early American canal engineering and state-backed commercial ambition.