Flowing through Potter and Cameron counties, First Fork Sinnemahoning Creek is a 33-mile tributary of Sinnemahoning Creek. Above Wharton, First Fork averages around 45-50 feet wide and substantially larger below Wharton. A 3.9-mile Delayed Harvest Artificial Lures Only section begins at the Route 872 bridge at Schoolhouse and extends down to the confluence with Berge Run.

Access along the DHALO, as well as many other parts of the stream, is generally excellent as Route 872 parallels First Fork from its mouth all the way to the town of Costello. In Costello, bear right onto First Fork Road to continue to the upper stretches of the stream. In its headwaters, you’ll find a good mix of stocked and wild fish, but downstream of Costello consists of primarily stocked trout, and downstream of Wharton becomes a decent smallmouth bass fishery during the summer months.