Harleysville is a census-designated place (CDP) in Montgomery County, Pennsylvania, United States. It is a suburb of Philadelphia. The population was 9,286 at the 2010 census. It is located mostly within Lower Salford Township and also in Franconia Township. Harleysville was settled by Pennsylvania Dutch in the 18th century and was named after Samuel Harley.
Harleysville was settled early in Pennsylvania's history, c. 1700.
The Klein Meetinghouse was listed on the National Register of Historic Places in 1973.
According to the United States Census Bureau, the CDP has a total area of 4.2 square miles (11 km2), all of it land.
Pennsylvania Route 63 (Main Street) and Pennsylvania Route 113 (Harleysville Pike) meet in Harleysville and provide access to other routes on the main grid. Interstate 476 is a five-minute drive via PA 63 from Harleysville to the Lansdale Interchange, on the Northeast Extension of the Pennsylvania Turnpike. Center City Philadelphia is less than 30 miles from Harleysville.