There are many access points including along PA highways 16, 34, 75, and Route 30 (The Lincoln Highway).
The Tuscarora Trail was originially thought up in the late 1960s and is composed of what used to be the Big Blue Trail in Virginia. It runs north all the way to the Darlington Trail on Blue Mountain just north of Carlisle on the west side of the Susquehanna River. The trail is 252 miles long and runs through Virginia, West Virginia, Maryland, and of course Pennsylvania. PA has the most amount of the trail with 110 of those miles inside it's border.
The trail is similar to the Appalachian Trail with a few steeper sections. Though the hiking never exceeds Class 2, you're sure to find some interesting places to play along the Mason-Dixon. If you plan on heading out of PA and to the south, you'll cross some interesting summits such as Hogback Mountain in Virginia at 3,358ft. high. The trail then rejoins the A.T. before heading south into Shenandoah National Park. There is a marathon held on the Tuscarora Trail and it runs the entire length in March depending on weather conditions. The trail is maintained by the Northern chapter of the Potomac Appalachian Trail Club.
Comfortable hiking shoes, water/food, wet weather gear, and a camera.