The Colossal Vail 50/50 is an adventurous ultra run on portions of the Arizona Trail near the community of Vail (24 miles southeast of Tucson). Starting and finishing at Colossal Cave Mountain Park, the 50-mile, 55K and Half-Marathon courses feature some of the greatest high desert trail running opportunities in this part of the state.

The gentle terrain, expertly built trail, and wide-open vistas made the first event in 2014 an instant hit. The Colossal Vail 50/50 utilizes some of the most recently completed sections of the Arizona National Scenic Trail between Saguaro National Park-East and the foothills of the Santa Rita Mountains. The course was designed by experienced members of the Tucson Trail Runners as a relatively fast trail ultra on rolling terrain with great scenery. Well-stocked aid stations, comprehensive emergency communications, excellent event swag, delicious finish line food, and much more await all who participate in the event.