Mystery Mountain Marathon & 12 Miler

Mystery Mountain Marathon & 12 Miler takes place in Chatsworth, Georgia, on October 18, 2026. The event offers two trail formats: a marathon (26.2 miles) and a 12-mile race (about 19.3 km). Start times were not listed at the time of writing, so confirm them with the organizer. The name points to mountain terrain, which in north Georgia usually means real climbing and technical footing.

A trail marathon on mountain trails is a different animal from a road marathon: you should expect your finish time to be well beyond your road PR and plan by effort, not pace. Build a 16-week block that includes long runs with sustained climbs and descents, and get comfortable hiking steep sections with purpose. The 12-mile race is a solid option if you want the same mountain feel in a shorter package, or if you are using the day as a stepping stone toward a longer trail race in the spring.