Great Falls

Great Falls is a series of rapids and waterfalls on the Potomac River, 14 miles upstream from Washington, D.C., on the border of Montgomery County, Maryland and Fairfax County, Virginia. Great Falls Park, managed as part of George Washington Memorial Parkway, is on the southern banks in Virginia, and Chesapeake and Ohio Canal National Historical Park parkland is along the northern banks of the river in Maryland. Both are operated by the National Park Service. The Potomac and the falls themselves are legally entirely within Maryland, with the state and county boundaries following the south bank of the river.

Scenic views are offered on both the Maryland side and the Virginia side. The Billy Goat Trail on Bear Island, accessible from Maryland, offers scenic views of the Great Falls, as do vantage points on Olmsted Island. There are overlook points on the Virginia side.

Source: Wikipedia