The Casselman River is the Youghiogheny River’s largest tributary beginning at the confluence of the North and South branches and joining the Yough about 10 river miles north of the Mason-Dixon Line at Confluence, Pennsylvania. It offers miles of good scenery and is relatively tame and makes a fine run for beginners. To start this trip, the Casselman is flat, deep, and narrow and winds through a pretty, pastoral valley. It will then leave the road and cut into a wooded gorge, rushing over continuous riffles formed by cobbles and small boulders. A very picturesque spot is at the old Casselman Bridge with its big, graceful stone arch and below this the easy rapids continue and by the time you reach Salisbury the river is mostly flat.