The Piasa
St. Louis, United States • 16 May 2026
The Piasa Trail Races
The Piasa is a trail running event held in the rugged bluffs and forested ravines of Pere Marquette State Park in Grafton, Illinois. Named after a mythical creature from Illiniwek legend, the race utilizes a course characterized by technical footing, long climbs, and steep descents near the confluence of the Mississippi, Missouri, and Illinois rivers.
Participants can choose from three distinct distances:
- 12.5 km - A shorter distance featuring sharp climbs.
- 25 km - A middle-distance course with sustained climbing and technical terrain.
- 50 km - The longest option involving over 4,000 feet of elevation gain.
The event offers two registration formats. The Solo Division is for individual runners, while the Buddy Division allows two runners to complete the journey together. The 50 km distance has a total time limit of 8 hours, concluding in the early afternoon.
Course records and navigation are available via the Visitor Center, and packet pickup is held both the day before the race and on the morning of the event. Participants encounter a landscape of deep woods and rocky cliffs. Recognition is provided for top overall finishers across all distances, as well as specific age groups and buddy teams, featuring custom artwork from local artists. Lodging and camping facilities are available on-site at the park lodge and designated campgrounds. Visit the organization's website for the most recent information.