Lycoming County, Pennsylvania, USA
County or equivalent
Location overview
Lycoming County covers a broad stretch of north-central Pennsylvania, with Williamsport as its county seat and largest city. The West Branch Susquehanna River cuts across a landscape of Appalachian ridges, forested plateaus, farms and narrow valleys, making it the state’s largest county by land area. Formed in 1795 from Northumberland County, Lycoming became a major lumber center during the 19th century as timber moved downriver to Williamsport. The county had about 112,600 residents in 2025. Manufacturing, health care, education, agriculture, forestry and outdoor recreation support its economy today.