Explore, Enjoy, and Protect the Planet

On The Trail — July 2012

Slippery Rock Gorge and Hell’s Hollow — A cool summer hike!

by Gary Thornbloom

McConnell's Mill State Park

caption here · Photo by Gary Thornbloom

Slippery Rock Gorge Trail is a rugged, beautiful, enchanting, and cool summer hike. The trail is in McConnells Mill State Park, Lawrence County. The terrain was shaped by glaciation. As glacial lakes drained and ice dams formed and broke, the landscape was carved into its present form. The trail will lead you from the bottom to the top of the gorge, several times!

The forest canopy consists of large deciduous trees, including basswood, cherry, oak, cucumber magnolia, tulip popular, and numerous beech trees defaced with graffiti. There are some impressive hemlocks as well as thick stands of small hemlock. There is lots of shade! Wild flowers would be worth seeing in the Spring, particularly along Hell’s Run. The trail is wide enough to avoid the short sections with stinging nettle and poison ivy.

Begin with an easy ½-mile walk on Hell’s Hollow Trail to the waterfall at its end. Despite its name — one account is that a lost military officer was hiking upstream in the dark and observed the glow of limestone kilns — this a trail for persons of all ages and skills.

Along the way we observed frogs sitting on boulders in the stream, minnows darting under small stones in the stream, depressions from sinkholes formed as limestone eroded away, and multiple exposures of fractured bedrock in the stream bed. This was prior to the three most notable features: the stream flows through a narrow flume that was formed underground, and was exposed once the roof collapsed; a limekiln, cut into the rock and brick lined, from the 1800s can be viewed from the top and entered from the bottom; and finally Hell’s Hollow Falls, a beautiful cascade that first drops over a vertical rock face and then over a larger drop spreading out in a bridal veil spray.

Return to where the Slippery Rock Gorge Trail is visible to the right and follow it for either a retrace from wherever suits you, or to Eckert Bridge if you set up a shuttle. This is a well worn trail, but it has some steep sections, notably the switchbacks in the last couple miles.

As you cross the first tributary of Hell’s Run notice the orange-stained stream that joins the clear stream. The orange stain is caused by acid mine drainage from an abandoned coal mine. As Hell’s Run flows over Vanport Limestone the mine acid from numerous abandoned mines is neutralized and thus Hell’s Run remains an exceptional value stream.

McConnell's Mill State Park

caption here · Photo by Gary Thornbloom

After the trail has dropped into, and then out of, a second tributary you can see the first of three natural limestone bridges. The first is best viewed from an overlook to the right of the trail and looking back up the hollow. A short distance beyond this the trail goes over the most dramatic of the bridges. This one is easily explored from both above and below. You can hear the sound of running water as you approach the third bridge. The water flows from a cave you can drop down and look into. The water flows under the limestone bridge, and flows over a small waterfall. The trail goes over the bridge.

These limestone outcroppings are a good place to look for walking fern. When the tips touch an moist spot they can attach and form a new plant. Thus, the fern “walks.” The fronds do not look like most ferns, and that should help you to identify them.

Slippery Rock Gorge Trail then crosses an unnamed tributary where there is an inviting log to sit on next to the stream. Avoid it because of the yellow jacket nest under it! In ½-mile the confluence of Hell Run and Slippery Rock Creek makes a nice lunch stop.

The trail has been been rolling but now the climbs become more frequent and steeper as the trail is at times along the creek and at times on the rim above. The trail parallels Slippery Rock Creek and eventually descends to the alluvial flood plain where the trail sign at Walnut Flats states the distance you have come, 4.1 miles from Hell’s Run parking, and the distance to Eckert Bridge, 2.1 miles.

Once you begin climbing again the trail is steeper, uses switchbacks, and passes several small waterfalls and rock outcroppings. There are views of the gorge and of Slippery Rock Creek.

This is a pleasant summer hike. Lots of flowing water. Nice shade from tall trees. Whether you are interested in historical sites, natural history, or in simply getting out for the day, you will enjoy exploring Hell’s Run and the Slippery Rock Gorge Trail.


Gary Thornbloom is the Chair of Sierra Club Moshannon Group and can be reached at bearknob@verizon.net