Joan Maloof, executive director of old forest growth network, recognized McConnell Mills as an old growth forest Monday, April 19, 2021.

McConnells Mill State Park, Lawrence County, encompasses 2,546 acres of the Slippery Rock Creek Gorge, which is a National Natural Landmark.

The park is open every day of the year, sunrise to sunset. Day-use areas close at dusk. The historic gristmill is open on a limited schedule.

The park has 11.2 miles of trails. Included are:

- Alpha Pass: This 1.5-mile trail begins at the Alpha Pass scenic vista and follows the east bank of Slippery Rock Creek, blue blazes, indicating more difficult hiking;

- Hells Hollow: This half-mile trail begins at the parking lot, follows and twice crosses Hell Run on its way to a Limekiln and Hell’s Hollow Falls, easiest hiking;

- Kildoo Trail: This 3-mile loop is south of the historic gristmill and begins at either end of the covered bridge, and entails more difficult hiking;

- Slippery Rock Gorge: This 6.2-mile trail begins jointly with Hell’s Hollow Trail at the parking lot and splits off just before the second footbridge, blue blazes, more difficult hiking.