Sioux City Mighty Mo Marathon
The Mighty Mo runs a flat, certified course through Iowa, Nebraska, and South Dakota along the Missouri River, with indoor staging in Sioux City.
Every link above goes to the race, its timing provider, or an official registration partner. Last checked July 24, 2026.
Quick facts
- Certified full and half marathon courses on a flat river route.
- Crosses Iowa, Nebraska, and South Dakota in one race.
- Indoor start and finish base at the Siouxland Expo Center, with post-race showers.
- Sunday marathon caps a three-day weekend with 5K, 10K, and kids races.
2026 Sioux City Mighty Mo Marathon registration
Registration for the 2026 Sioux City Mighty Mo Marathon runs through the official registration page at runsignup.com.
About the Sioux City Mighty Mo Marathon
Sioux City's marathon anchors a three-day September race weekend, with the full and half on Sunday after shorter races on Friday and Saturday. The draw is a flat, certified three-state course and unusually practical logistics, including an indoor staging area at the Siouxland Expo Center.
Course
The course follows the Missouri River Trail and touches Iowa, Nebraska, and South Dakota in a single morning. It is flat and built for speed, with paved trail miles, multiple aid stations, and a start and finish based at the Siouxland Expo Center.
Race-day weather
Mid-September mornings in Sioux City are often cool, but the river valley can turn warm and bright by late morning. Wind along open trail sections is the most common stressor, so even effort beats chasing splits into a headwind.
Past Sioux City Mighty Mo Marathon dates and results
| Year | Date | Status | Results |
|---|---|---|---|
| 2026 | Sunday, September 13, 2026 | Upcoming | — |
Sioux City Mighty Mo Marathon FAQ
When is the Sioux City Mighty Mo Marathon?
The 2026 Sioux City Mighty Mo Marathon is on Sunday, September 13, 2026.
How do I register for the Sioux City Mighty Mo Marathon?
Register for the Sioux City Mighty Mo Marathon through the official registration link: marathonscout.com/go/mighty-mo-marathon/register. It opens the race registration page at runsignup.com.
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