U.S. Route 6 (US 6) travels east–west near the north edge of the U.S. state of Pennsylvania from the Ohio state line near Pymatuning Reservoir east to the Mid-Delaware Bridge over the Delaware River into Port Jervis, New York. It is the longest highway segment in the Commonwealth. Most of it is a two-lane rural highway, with some freeway bypasses around larger towns. Except east of Dunmore, where it is paralleled by Interstate 84 (I-84), it is the main route in its corridor. What is now I-80—the Keystone Shortway—was once planned along the US 6 corridor as a western extension of I-84. The corridor was originally the Roosevelt Highway from Erie, Pennsylvania to Port Jervis, New York, designated Pennsylvania Route 7 (PA 7) in 1924. The PA 7 designation soon disappeared, but as US 6 was extended and relocated, the Roosevelt Highway followed it. The Pennsylvania section of US 6 was renamed the Grand Army of the Republic Highway in 1946; this name was applied to its full transcontinental length by 1953.US 6 meets with U.S. Route 19 near Meadville, where it turns north with US 19 to a point east of Edinboro. There it turns east (while U.S. Route 6N heads west to U.S. Route 20 at West Springfield) and passes through the Northern Tier of Pennsylvania. At Towanda it turns more southeasterly to reach Dunmore, then turning back northeast out of Dunmore to Carbondale and generally east and southeast to New York. US 6 fully encompasses two Pennsylvania Scenic Byways: the Gateway to the Endless Mountains Scenic Byway along the bypass of Tunkhannock and the Governor Casey Scenic Byway along the freeway portion in Lackawanna County between I-81 in Dunmore and PA 247 in Jessup.At 403 miles in length, US 6 is the longest numbered highway in Pennsylvania.
