Pennsylvania Route 320

Pennsylvania Route 320
Route information
Maintained by PennDOT and Lower Merion Township
Length	18.832 mi[1] (30.307 km)
Major junctions
South end	US 13 / PA 291 in Chester
Major intersections	US 13 Bus. in Chester I-95 in Chester PA 252 in Nether Providence Township PA 420 in Springfield US 1 in Springfield PA 3 in Broomall US 30 in Villanova I-76 in Gulph Mills
North end	PA 23 in Swedeland
Location
Country	United States
State	Pennsylvania
Counties	Delaware, Montgomery
Highway system
Pennsylvania State Route System Interstate US State Scenic Legislative
← PA 319 → PA 321

Pennsylvania Route 320 (PA 320) is a north–south state highway in southeastern Pennsylvania. The southern terminus of the 18.8-mile (30.3 km) long route is at U.S. Route 13 (US 13)/PA 291 in Chester. The northern terminus is at PA 23 in Swedeland. The route passes through suburban areas in Delaware and Montgomery counties to the west of Philadelphia, serving Swarthmore, Springfield, Broomall, Villanova, and Gulph Mills. PA 320 intersects many important highways including US 13 Business (US 13 Bus.) and Interstate 95 (I-95) in Chester, US 1 in Springfield, US 30 in Villanova, and I-76 in Gulph Mills. PA 320 runs parallel to I-476 (Mid-County Expressway) for much of its length and crosses it four times. Even though there are no direct interchanges between I-476 and PA 320, several roads that intersect PA 320 provide access to I-476.

The southernmost part of PA 320 was built as part of the Providence Road in 1684. PA 320 was first designated by 1928 between US 13 (now US 13 Bus.) in Chester and PA 23 in Lower Merion Township. PA 320 was extended south to PA 291 by 1940. The route was extended north to US 202 in Bridgeport via West Conshohocken by 1960. By 1967, the northern portion of the route was realigned to its current routing, replacing parts of PA 23 Alternate (PA 23 Alt.) and PA 23 and following part of former PA 123, with PA 23 rerouted to replace the part of PA 320 from southeast of West Conshohocken to Bridgeport. The nearby I-476 opened in 1991, reducing traffic levels on PA 320.