Ardmore is an unincorporated community and census-designated place (CDP) spanning the border between Delaware and Montgomery counties in the U.S. state of Pennsylvania. The population was 12,455 at the 2010 census and had risen to 13,566 in the 2020 Census. Ardmore is a suburb on the west side of Philadelphia, within Lower Merion Township in Montgomery County and Haverford Township in Delaware County. Originally named "Athensville" in 1853, the community and its railroad station were renamed "Ardmore" in 1873 by the Pennsylvania Railroad, on whose Main Line, west out of Philadelphia, Ardmore sits at Milepost 8.5. The Autocar Company moved its headquarters to Ardmore in 1899 and constructed a factory on the edge of the downtown area. The factory closed in 1954; during demolition in 1956, a