In Pittsburgh you’ll make the choice to stay on the main route or to follow the Philadelphia Alternate. The route uses the Great Allegheny Passage, a multi-use trail that primarily follows railroad corridors from Pittsburgh to Cumberland. It traverses four tunnels; the longest is the Big Savage Tunnel at 3,294 feet. Grades along the trail are less than 2 percent. In Cumberland the route continues onto the C&O Canal Trail and follows the Potomac River eastward along the Maryland/West Virginia state border. At Hagerstown the route heads northeast past Gettysburg National Military Park, crosses the Susquehanna River, and enters Lancaster County, known as “Pennsylvania Dutch Country.”