Tantallon is an unincorporated community in Prince George's County, Maryland, United States, and is a part of the census-designated place (CDP) of Fort Washington.

[5] Tantallon began in the 1960s as a country-club community of homes in a variety of architectural styles, and includes an 18-hole golf course, boat marina, and private swimming pool.

The adjacent Hatton Point area, as well as nearby historic Fort Washington National Park, have very scenic views of the river.

The bi-county parks commission's Harmony Hall Recreation Center, and metrobus commuter service to Washington, D.C., are nearby.

Tantallon is located at 38.7 degrees north, 77.0 degrees west (38.724, −77.01);[6] or approximately 12 miles south-southeast of Washington, D.C.[7] The elevation for the community is 39 feet above sea level.