The river rises in the Pocono Mountains of northeastern Pennsylvania, in several ponds in Lehigh Township, Wayne County, approximately southeast of Scranton. It flows initially southwest, through southern Lackawanna County, through Francis E. Walter Reservoir. Near White Haven it turns south, following a zigzag whitewater course through Lehigh Gorge State Park to Jim Thorpe, then southeast, past Lehighton. Southeast of Lehighton, it passes through Blue Mountain in a narrow opening called the Lehigh Gap.