The lock, located at towpath mile-marker 19.7, is near River Road in Montgomery County, Maryland.

George was an avid fisherman, and once hosted President Grover Cleveland for several days of fishing near the lock.

[4] Portions of the canal (close to Georgetown) began operating in the 1830s, and construction ended in 1850 without reaching the Ohio River.

Because portions of the Potomac can be shallow and rocky as well as subject to low water and floods, the river could not serve for reliable navigation and a continuous canal on land was necessary.

By 1859, about 83 boats per week were using the canal to transport coal, grain, flour, and farm products to Washington and Georgetown.

Starting in Baltimore and adding line westward, the B&O Railroad eventually reached the Ohio River and beyond.

[10] The damage and continued competition from railroads and trucks led to the decision to close permanently later that year.

[12] Construction of the lock house began in October 1829, and was finished April 1830 at a cost of $853.20 (equivalent to $24,412 in 2023).

[14] By June 1832, a 22-mile (35 km) section of the canal was operating between Georgetown and Seneca, which includes Lock 22.

[34] The Muddy Branch, a tributary to the Potomac River, is less than a half mile (0.8 km) walk on the canal towpath.

[32] Additional bird watching is available nearby along the towpath at the Pennyfield Lock Neighborhood Conservation Area, a 1.9 acre (0.77 ha) park with boat ramp maintained by Montgomery County.

[35] The 40-acre (16 ha) Dierssen Waterfowl Sanctuary is also adjacent to the canal towpath and a favorite of bird watchers.