National Parks near Grosses Gap Trail, Union County, Pennsylvania Grosses Gap Trail Main Page HIGH QUALITY TOPO MAP, CLICK HERE More Information about Grosses Gap Trail, Union County, Pennsylvania Nearest metro area is Lewisburg, Pennsylvania Click here for more outdoors activities near Lewisburg, Pennsylvania General Camping Information List of nearby National Parks: Catoctin Mountain Park, Thurmont - MD, 78.5 miles away Appalachian National Scenic Trail, Harpers Ferry - WV, 101 miles away Potomac Heritage National Scenic Trail, McLean - VA, 101 miles away Greenbelt Park, Greenbelt - MD, 106.1 miles away Glen Echo Park, McLean - VA, 107.1 miles away * Distances listed are direct linear distances, actual travel distance may be different. Go to Pennsylvania Outdoors Index