After cutting through rural Mercer and Venango counties, US 62 reaches the twin industrial towns of Franklin and Oil City.

Immediately before entering Oil City, the roads split, with US 62 branching off to cross the Allegheny River over the Petroleum Street Bridge and serve the south side of town.

After crossing this 1995 girder structure, which replaced a 1910 truss bridge, the highway remains four lanes until leaving the municipality.

The Allegheny River is only rarely out of sight as the highway winds its way through Venango and Forest Counties, crossing from the south bank to the north by way of the Hunter Station Bridge, an unusual 1934 truss design.

The route passes through the Allegheny Islands Wilderness, crosses the river again via the Irvine Bridge, and subsequently joins with US 6 via a trumpet interchange to form part of the freeway bypass of Warren, which was constructed in 1969.