Pennsylvania Route 18

PA Route 18
Route of PA 18 highlighted in red
Route information
Maintained by PennDOT
Length:	205 mi (330 km)
Major junctions
South end:	WV 69 near Garrison
	I-70 near Washington US 22 near Frankfort Springs I-376 near Monaca I-76 / Penna Turnpike in Big Beaver I-376 near West Middlesex I-80 / I-376 / PA 760 near West Middlesex I-90 near Platea
North end:	PA 5 in Lake City
Location
Counties:	Greene, Washington, Beaver, Lawrence, Mercer, Crawford, Erie
Highway system
Pennsylvania State Route System Interstate US State Scenic Byways Legislative ← PA 17 US 19 →

PA Route 18 Truck
Location:	Washington, Pennsylvania

PA Route 18 Truck
Location:	New Castle, Pennsylvania
Existed:	2013–present

Pennsylvania Route 18 (PA 18) is a major north–south highway in Western Pennsylvania whose southern terminus is at West Virginia Route 69 at the state line in Greene County, Pennsylvania near the village of Garrison, while the northern terminus is at PA Route 5 in Lake City, Pennsylvania. At a length of 205 miles (330 km), PA 18 is one of the few state routes in Pennsylvania — north–south or east–west — to traverse the entire state. It also has the distinction of being the longest state route in Pennsylvania.

Traveling northward from West Virginia Route 69 at the West Virginia state line, Route 18 winds through rural Greene County, passing through the villages of Garrison, New Freeport, Nettle Hill, White Cottage, Woodruff, and Holbrook, before making its first junction with another state highway, PA Route 21, just west of the village of Rogersville and over 15 miles (24 km) from the state line. Here the two routes overlap for nearly 6 miles (9.7 km), winding east-northeast through Rogersville and the village of East View, crossing the South Fork of Ten Mile Creek numerous times before reaching the village of West Waynesburg. At this point, Route 18 leaves the concurrency and turns northwest, traveling 12 miles (19 km) to the county line, following along Browns Creek, and passing through the villages of Rees Mill, Sycamore, and Nineveh.

Route 18 enters Washington County, and intersects with the eastern terminus of PA Route 231 and turns to the northeast and traveling over 5 miles (8.0 km), passing near the villages of Old Concord and Sparta. Next, the route meets PA Route 221, and the two overlap for just over a mile, heading northwest through the village of Prosperity. After the village, Route 18 leaves the concurrency and heads northward through the villages of Van Buren, Lagonda, and Gabby Heights as it approaches the city of Washington nearly 10 miles (16 km) later. In Washington, Route 18 briefly overlaps with US 40, and the routes head west, intersect with the western terminus of PA Route 136, and then turn northwest. US 40 then leaves the concurrency, and nearly a mile later, Route 18 interchanges with I-70, connecting via city streets to the entrance and exit ramps. Before departing the city, 0.4 miles (0.64 km) later, the route intersects with the eastern terminus of PA Route 844, turns northward, and passes through the village of Oak Grove. Route 18 passes through the village of Gretna 8.5 miles (13.7 km) later and then overlaps with PA Route 50 for 0.5 miles (0.80 km) a couple miles west of the village of Hickory before continuing north-northwest. The route then passes by the village of Atlasburg and through the village of Slovan before reaching the borough of Burgettstown 7.5 miles (12.1 km) later. Route 18 meets US 22 nearly 4 miles (6.4 km) north of the borough, and then passes through the village of Florence at Old US 22 before reaching the county line just over 3 miles (4.8 km) later.