Mystery Mountain Marathon & 12-Miler
Chatsworth, United States • 18 Oct 2026
Mystery Mountain Marathon and 12-Miler
The Mystery Mountain event offers two trail races through Fort Mountain State Park near Chatsworth, GA. The marathon covers rugged terrain with about 5,500 feet of elevation gain and uses single track, mountain bike, and horse trails while passing the rock wall at the mountain summit that is over 1,000 years old. The weekend includes a post-race gathering by the lake.
The event location is Fort Mountain State Park, approximately 90 miles north of Atlanta and 50 miles southeast of Chattanooga. Registration opens April 17, 2026. Enter before September 18 for a guaranteed shirt size. GUTS membership is available for $15 per year and offers a $5 discount on GUTS races.
Cutoffs and time limits are specified for runner safety. The 12-miler has a 6-hour time limit with a 3.5-hour cutoff at the park entrance (about 8 miles). The marathon has an 8-hour time limit with cutoffs at the park entrance (about 8 miles), Power Line Aid Station (about 11 miles), Far Out Aid Station (about 18.9 miles), and Last Gasp (about 22.3 miles). Race direction and medical staff may remove runners if continuing is judged unsafe.
Awards are given to the top three men and women overall, plus first place masters and grandmasters for both men and women.
Distances Visit the organization's website for the most recent information.
- Marathon - about 5,500 feet elevation gain, mixed single track and wider trails.
- 12-Miler - trail race with a 6-hour limit and an early cutoff near 8 miles.