14th Annual Rock CF Rivers Half Marathon, 5K & NEW

Sunday, March 22nd, 2026

Rock CF Rivers Half Marathon, 5K & NEW 15K

We are back for a lap around beautiful Grosse Ile, Michigan!

Click Here for 2025 Race Results! Race Photos Here!

Rock CF is hitting the island for the 15th Annual Rivers Half Marathon, 5K Run/Walk & 15K on Sunday, March 22nd, 2026 for all to come and help us outrun cystic fibrosis!

Rock CF 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.

$85 8:00AM EDT - 11:30AM EDT Registration Opens September 8, 2025 at 12:00am EDT

$40 8:15AM EDT - 11:30AM EDT Registration Opens September 8, 2025 at 12:00am EDT

$50 Registration Opens September 8, 2025 at 12:00am EDT

$70 8:00AM EDT - 11:00AM EDT Registration Opens September 8, 2025 at 12:00am EDT

Race Caps for 2025!

Half Marathon - 800 (SOLD OUT!)

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