Oldtown is an unincorporated community and census-designated place (CDP) in Allegany County, Maryland, United States, along the North Branch Potomac River.

Shortly after his release from prison in Pennsylvania for advocating Maryland's claims, Cresap moved west to the sparsely settled frontier.

Cresap and the Delaware chief Nemacolin opened a road westward under the auspices of the Virginia and Maryland speculators of the Ohio Company once they received a charter.

Oldtown is connected by a one-lane low-water toll bridge to Green Spring in Hampshire County, West Virginia.

The B&O Railroad, now CSX, continues to be a major carrier, and it is used daily by Amtrak's Capitol Limited between Washington, DC and Chicago.

The line was officially abandoned as part of the "Chessie System" consolidation, and all WM trains began running on the nearby B&O.