The Potomac Wharf Branch was used to carry coal to flat-bottom Potomac River boats, and to canal boats, before a canal wharf facility for the Chesapeake and Ohio Canal (C&O Canal) was completed. The flat-bottom boats ferried coal down the Potomac to Georgetown, Washington, D.C. and Alexandria, Virginia during the Spring, when the water level was high enough for navigation. After the C&O Canal reached Cumberland, canal boats could enter the Potomac River through the guard locks. The original Potomac River wharf had been built by John Galloway Lynn of Cumberland, and was known as the Lynn Wharf. It ran along what now is Avirett Avenue. It was deeded to the Maryland Mining Company in 1849.