Thunder Chicken 100K Stage Races

Thunder Chicken 100K Stage Races

The Thunder Chicken 100K Stage Races is a three-day trail running event hosted at Beulah Shelter in Greensfelder County Park, in Wildwood, Missouri. It is presented by Terrain Trail Runners. The event consists of stage races held on consecutive days, with courses utilizing the trail systems of Greensfelder Park, Rockwoods Range, and Rockwoods Reservation.

Participants can register for several options:

• Thunder Chicken 100K: A three-day cumulative race covering approximately 72 miles.
• Thunder Chicken 21Mi: A single-stage race.
• Thunder Chicken 26Mi: A single-stage race.
• Thunder Chicken 25K: A single-stage race.
• Thunder Chicken Pick 2: Combinations of two of the single-stage races.

Each day's stage has a distinct course. Stage 1 (21-ish miles) is the "Tour de Rockwoods Range" with about 2,650 feet of elevation gain. Stage 2 (26-ish miles) is the "Tour de Rockwoods Reservation" with about 4,150 feet of elevation gain. Stage 3 (25K-ish) is the "Tour de Greensfelder" with about 1,850 feet of elevation gain. The courses feature technical terrain with rocks, roots, creek crossings, and climbs.

Race registration includes a custom finisher medal, a custom T-shirt (if registered by April 19, 2026), and post-race snacks and beer. Participants who complete all three days receive a custom belt buckle. The event is part of the Trail Mix Fund, which pays registration fees for runners from under-served or under-represented groups.

This is a cup-free event, meaning no disposable cups are provided at aid stations or the finish. Runners must bring their own drinking receptacle. The event also encourages participants to bring their own mess kit (plate and spork) for post-race meals to support a zero-waste pledge. Tent and RV camping with showers is available at Greensfelder County Park. Visit the organization's website for the most recent information.