Boucle extérieure des montagnes Catoctin est un itinéraire 18.6 km (27 000pas) localisé près de Thurmont, Maryland, Etats-Unis. Cet itinéraire a un gain de hauteur autour de 717 m et est classé difficile. Trouvez plus ditinéraires comme celui-ci sur lApp Pacer.
Start at the lower parking area near the park headquarters (before the visitors center). The route is 11.5 miles in length with a lot of up and down. About half way through at the falls the stream may or may not be crossable. There is no set trail there so need to be careful.