U.S. Route 13 (US 13) is a United States Numbered Highway running from Fayetteville, North Carolina, north to Morrisville, Pennsylvania. The route runs for 49.359 miles (79.436 km) through the Delaware Valley in the U.S. state of Pennsylvania. The route enters the state from Delaware in Marcus Hook, Delaware County. It continues northeast through Delaware County, passing through the city of Chester before heading through suburban areas along Chester Pike to Darby. US 13 enters the city of Philadelphia on Baltimore Avenue and runs through West Philadelphia to University City, where it turns north along several city streets before heading east across the Schuylkill River along Girard Avenue. The route turns north and heads to North Philadelphia, where it runs northeast along Hunting Park Avenue. US 13 becomes concurrent with US 1 on Roosevelt Boulevard, continuing into Northeast Philadelphia. US 13 splits southeast on a one-way pair of streets before heading northeast out of the city on Frankford Avenue. The route continues into Bucks County as Bristol Pike, heading northeast to Bristol, where it turns into a divided highway. US 13 becomes a freeway in Tullytown and continues north to its terminus at US 1 in Falls Township, near Morrisville. US 13 roughly parallels Interstate 95 (I-95) through its course in Pennsylvania.

Marcus Hook is a borough in Delaware County, Pennsylvania, United States. The population was 2,397 at the 2010 census. The current mayor is Gene Taylor. The borough calls itself "The Cornerstone of Pennsylvania". The 2005 film One Last Thing... was set and partially filmed in Marcus Hook.