16th Annual Rock CF Rivers Half Marathon - Half Marathon
Also in this race
These events were grouped as one card in discovery—pick another distance or date without going back.
External Event
Distance
13.1 mi
Pace
All paces
Terrain
Road
Difficulty
All Levels
About this run
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.
Typical conditions
For events around March 2027 in Grosse Ile, MI, United States: Typical spring conditions in this region — mornings can still be cool; confirm start-time guidance on the official page.
How to prepare
Half marathon prep usually includes a weekly long run that builds toward 16–20 km, plus easy runs for recovery. Confirm packet pickup and start procedures on the official registration page.
Plan longer races for 2026Getting there
This event is listed in Grosse Ile, MI, United States. Confirm the exact start venue, parking, and transit options on the official registration page.
Registration is handled by the official event organizer
Know a local group? Host a community run in Grosse Ile
Also in this race
- Mar 21, 2027 · 1:00 PM
- Mar 21, 2027 · 1:00 PM
- Mar 21, 2027 · 1:00 PM (this one)
- Mar 21, 2027 · 1:15 PM