Pennsylvania Route 18
Route of PA 18 highlighted in red | ||||
| Route information | ||||
| Maintained by PennDOT | ||||
| Length | 205 mi (330 km) | |||
| Tourist routes | Crawford Lakelands Scenic Byway | |||
| Major junctions | ||||
| South end | WV 69 at the West Virginia state line | |||
| US 40 in Washington I-70 near Washington US 22 near Frankfort Springs US 30 near Harshaville 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 US 20 near Girard | ||||
| North end | PA 5 in Lake City | |||
| Location | ||||
| Country | United States | |||
| State | Pennsylvania | |||
| Counties | Greene, Washington, Beaver, Lawrence, Mercer, Crawford, Erie | |||
| Highway system | ||||
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Pennsylvania Route 18 (PA 18) is a major north–south highway in Western Pennsylvania whose southern terminus is at the West Virginia state line, where it continues as WV 69, while the northern terminus is at PA 5 in Lake City. At a length of 205 miles (330 km), PA 18 is the only state route 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.