The Mid State Trail (MST) is a 518 km (323 mile) long main trail network with many side trails located in the Ridge-and-valley Appalachians and Allegheny Plateau of Central Pennsylvania. It is known as "The Wildest Trail in Pennsylvania". In 2006, MST was announced as part of the Great Eastern Trail network of footpaths intended to extend from Alabama to New York State.
The Mid State Trail extends from the Maryland border to the New York border, bisecting the middle of Pennsylvania. The southern end of the MST is found on the Mason-Dixon line on route PA326. The northern terminus is located just north of Lawrenceville, PA. The MST is primarily on public land; state forests, state game lands and state parks. MST uses private lands by permission on occasion, generally closer to the Maryland and New York borders.
The MST is maintained by the Mid State Trail Association.