Thunder Chicken 100K Stage Races

Thunder Chicken 100K Stage Races

Thunder Chicken 100K Stage Races is a three-day trail running stage event held at Greensfelder County Park, Beulah Shelter, in western St. Louis County, Missouri. The race links trail systems in Greensfelder Park, Rockwoods Range and Rockwoods Reservation and uses technical singletrack, creek crossings, bluffs and dense forest.

Distances:

• Stage 1 - 21-ish miles Tour de Rockwoods Range
• Stage 2 - 26-ish miles Tour de Rockwoods Reservation
• Stage 3 - 25K-ish Tour de Greensfelder

Stage 1 covers varied terrain with steep grades, rocks, roots and about 2,650 feet of cumulative elevation gain. Stage 2 is a longer out-and-back with sustained climbing, technical footing and about 4,150 feet of elevation gain. Stage 3 emphasizes faster singletrack with punchy technical sections and about 1,850 feet of elevation gain.

There will be a minimum of one aid station per stage. Registration includes a custom cotton/poly lifestyle t-shirt for those who register by April 3, 2027; later registrants receive alternative swag in limited quantities. Post-race provisions vary by stage, and All 3 Day finishers receive a custom belt buckle while individual stage finishers receive medals. Overall awards for All 3 Day finishers are given in male, female and non-binary categories.

The event is cup-free and follows a zero waste sustainability pledge. The race joined the Trail Mix Fund partnership in December 2025, which can cover registration fees for eligible runners. Visit the organization's website for the most recent information.