High on the Allegheny Plateau, Potter County is the source of three major river systems. Eleven miles northeast of Coudersport, on a hilltop near Raymond, the watersheds converge: water from the north side forms the Genesee River and flows north to the St. Lawrence River, a spring-fed stream nearby runs west to Coudersport and becomes the Allegheny River on its way to the Gulf of Mexico, and the headwaters of Pine Creek flow east to the Susquehanna River and then to the Chesapeake Bay. Rough terrain and a scarcity of navigable rivers slowed travel and made Potter County one of the last parts of Pennsylvania to be settled, and Coudersport did not incorporate until 1848. Although many early settlers came to farm, the densely forested land and short growing season led many into lumbering. In the mid-1800s, getting logs to market was difficult because local rivers were too narrow for log rafts, so Coudersport-area lumbermen floated loose logs, mostly white pine, down the Allegheny River, while farther south tributaries such as Pine Creek and Sinnemahoning Creek carried logs to Williamsport's sawmills. Because logging depended on waterways, cutting first centered near streams, but railroads in the late 1800s opened the region's extensive hemlock forests, and hundreds of miles of track spread from large sawmills at Galeton, Austin, and Cross Fork while also supplying hemlock bark to local tanneries, including the world's largest tannery at Costello in its time.