Black Rock Mill Access provides parking and trailhead access to the Greenway Trail system along Great Seneca Creek in Seneca Creek State Park, with interpretive exhibits about the historic 1816 mill.

The location offers hiking and biking trail access in both directions—approximately 1. 1 miles south to Route 28 and multiple miles north toward Lake Clopper—with relatively few developed amenities in the surrounding area.

Paddlers can access Great Seneca Creek for Class I-II canoeing and kayaking during wet weather periods, with a recommended take-out at Riley's Lock approximately 2 hours downstream.