The Patowmack Canal, sometimes called the Potomac Canal, is a series of five inoperative canals located in Maryland and Virginia, United States, that was designed to bypass rapids in the Potomac River upstream of the present Washington, D.C., area. The most well known of them is the Great Falls skirting canal, whose remains are managed by the National Park Service since it is within Great Falls Park, an integral part of the George Washington Memorial Parkway.

The Potomac River is a major river in the Mid-Atlantic region of the United States that flows from the Potomac Highlands in West Virginia to the Chesapeake Bay in Maryland. It is 405 miles (652 km) long, with a drainage area of 14,700 square miles (38,000 km2), and is the fourth-largest river along the East Coast of the United States and the 21st-largest in the United States. More than 5 million people live within its watershed.