The park, comprised of 6,300 acres, extends along 14 scenic miles of Seneca Creek, as it winds its way to the Potomac River. The Clopper Day-Use Area contains many scenic areas, including the 90-acre Clopper Lake, surrounded by forests and fields. Picnicking, boat rentals, and ​trails are just some of its recreational opportunities. A restored 19th century cabin and a self-guided path interpret the history of the area. Over 50 miles of trails are open for hiking, horseback riding and bicycling which wind through a variety of habitat.​​

Note: Swimming and wading are not permitted in Clopper Lake at Seneca Creek State Park. The closest Maryland State Parks with lifeguarded lake swimming are Cunningham Falls State Park and Greenbrier State Park. Wading is permitted at your own risk in Great Seneca Creek, the free flowing creek which runs the length of Seneca Creek State Park.