In 148 days · Sun, Mar 21, 2027
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Sunday, March 21st, 2027
23270 E River Rd, Grosse Ile MI
Half · 15K · 5K
32–47°F · some rain risk
See last 10 years
On this date: rain 0 of the last 10 years
2026
30–41°F
dry
2025
29–51°F
dry
2024
22–33°F
dry
2023
35–47°F
dry
2022
35–54°F
dry
2021
30–50°F
dry
2020
26–34°F
dry
2019
35–48°F
dry
2018
29–39°F
dry
2017
30–55°F
dry
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About this race
The 16th Annual Rock CF Rivers Half Marathon, 15K, and 5K is coming back to the island of Grosse Ile, Michigan on Sunday, March 21st, 2027 for all to come and help us outrun cystic fibrosis! Starting from the Grosse Ile High School, enjoy the flat-and-fast course en route to chasing a personal best, experiencing your first half marathon, or taking in the scenic views of the Detroit River with friends & family at one of Michigan's premier spring races.
Course map
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