We are coming back to the beautiful island of Grosse Ile, Michigan for the 15th Annual Rivers Half Marathon, 15K (NEW!), and 5K Run/Walk on Sunday, March 22nd, 2026 for all to come and help us outrun cystic fibrosis!
The Rock CF Foundation is a community, thousands strong, changing the face of what living with cystic fibrosis looks like and giving those living with CF the tools to not only survive, but thrive. 100% of all proceeds support the mission of the Rock CF Foundation.
Half Marathon
Price:
$85
Time:
8:00AM EDT
- 11:30AM EDT
Registration ends March 22, 2026 at 7:45am EDT
5K Run/Walk
Price:
$40
Time:
8:15AM EDT
- 11:30AM EDT
Registration ends March 22, 2026 at 8:00am EDT
Race Caps for 2026!
Half Marathon - 800
15K (NEW!) - 300
5K Run/Walk - 500
Race Weekend!
Saturday, March 21st
Race Expo @ Grosse Ile HIGH School
12:00 PM - 6:00 PM
Sunday, March 22nd
Half Marathon & 15K - 8:00 AM
Grosse Ile HIGH School
5K Run/Walk - 8:15 AM
Grosse Ile Naval Hangar
Interested in Volunteering?
Looking to get involved with the race in 2026? Sign up for one of our many volunteering opportunities available on race day and the expo!
Volunteer
Half Marathon
Price:
$85
Time:
8:00AM EDT
- 11:30AM EDT
Registration ends March 22, 2026 at 7:45am EDT
5K Run/Walk
Price:
$40
Time:
8:15AM EDT
- 11:30AM EDT
Registration ends March 22, 2026 at 8:00am EDT
