St. Charles gives you a small-town marathon on the Missouri River, starting and finishing on Riverside Drive beside the brick storefronts of historic Main Street. The course is flat for nearly ten miles, climbs through a two-mile hilly stretch, and then settles onto the Katy Trail around mile 12 for an out-and-back where the surface turns to packed dirt and the noise drops to footsteps and river birds. You cross a grated bridge twice, so watch your footing. The final mile is downhill into Frontier Park, between Main Street and the river. The race started in 2011 and is run by the county's Economic Development Council; about 500 marathoners finished in 2025. Note the date: it is now Sunday, November 8, 2026, so plan for a cool morning rather than October warmth.
Starts and finishes on the Missouri River at 500 S. Riverside Dr. in historic St. Charles, flat for nearly ten miles, a two-mile hilly stretch, then an out-and-back on the unpaved Katy Trail from about mile 12, with a downhill final mile into Frontier Park.
Open now on RunSignup (as of 2026-10-13). Prices and deadlines not captured. Organized by the Economic Development Council of St. Charles County, a nonprofit. Register ↗
- MO' Cowbell was started in 2011. ↗
- The marathon joins the Katy Trail around mile 12 and crosses a grated bridge twice. ↗
- About 14.5 miles are paved road with the rest on dirt trail; elevation gain and loss are 520 ft. ↗
- 503 runners finished the marathon in 2025; 2.4% ran Boston-qualifying times in each of 2023, 2024 and 2025. ↗
- The course is flat for nearly ten miles before a two-mile hilly stretch, and the last mile is downhill. ↗
Checked 2026-10-13. Always confirm on the official site before booking travel.