In 202 days · Tue, May 11, 2027
Don't let race day sneak up
One email during race week. That's it.
Tuesday, May 11th, 2027
1272 Council Oak Drive, Sioux City IA
Marathon · Half · 10K · 5K
51–72°F · some rain risk
See last 10 years
On this date: rain 4 of the last 10 years
2026
45–84°F
dry
2025
64–90°F
dry
2024
49–78°F
dry
2023
62–79°F
rain
2022
64–86°F
rain
2021
37–60°F
dry
2020
34–55°F
dry
2019
41–62°F
rain
2018
49–63°F
rain
2017
49–66°F
dry
Best months to race in Iowa →
About this race
World's Best Marathon & Half Series!
No Time Limits
Great Food
Award-Winning Medals
Loony Community!
We RUN this country, TOGETHER!
Event details and schedule
Thanks for running with Mainly Marathons! Take a look at our website for additional details about this series and our other series of races.
Also, join our Facebook group to stay up-to-date with our loony adventures: Main Group and Prairie Series.
If you're interested in some Mainly Merch, check out our online store HERE. We'll offer some items (hats, stickers, magnets, mugs, etc.) in-person at the races, the Mainly Merch store best option for a variety of fun designs and quality merchandise to showcase your loonacy!
If you have any questions, email [email protected]
We RUN this country, TOGETHER!
Course map
Train with a club
Run clubs near Sioux City to train with before race day.
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