The Glacier Ridge Trail courses (including 5-person relay) are out-and-back style courses. The 30K and 50K courses largely follow the blue-blazed Glacier Ridge/North Country Trail between the west end of Moraine State Park and the Jennings Environmental Education Center near Slippery Rock, PA. The Glacier Ridge Trail (GRT) is a local designation for that part of the more extensive North Country Trail system that passes through Moraine State Park. Trail markers use the North Country Trail designation, so if you notice this out on the course, don't be confused, they are one and the same. The 50-mile course uses the GRT, as well as a system of snowmobile/horse trails to the east of Lake Arthur.