From Millersburg take Route 25 north towards Berrysburg. Head through Berrysburg and continue into Gratz. Once you reach the center of Gratz there will be a road sign to turn left towards Klingerstown. From here continue for three miles with the gap in sight and park at the base of the mountain.
From the base of the mountain look for a dirt road. This road is an old logging road which heads up the ridge line on some steep and rocky terrain. Before you get to the top, you'll hike through a little hollow where old strip mining occured and the rock walls will rise on your right (south) in heights up to 30 feet. These ledges are quite impressive and afford a few nice scrambling opportunities.
Once you reach the top of the ridge you'll be hiking on almost a knife edge of rocky ledges. The route will continue to head east on the ridge line and the farther you go, the broader the ridge gets. Some nice views are attainable to the south thanks in part to some timbering that has occured within the last five years. If you hike this route in Spring you are very likely to see a turkey running through the patches of flowering dogwood trees. Depending on how far out the ridge you go, you can determine the distance of your hike. You'll gain a little bit over 800 feet in going from the gap to the top of the ridge.
Comfortable hiking boots, food/water, trekking poles, and a camera.