About the Rock CF Thumb Coast Marathon, Half Marathon & 5K
The marathon starts in downtown Caseville and runs east along the Saginaw Bay shoreline of Lake Huron, finishing in downtown Port Austin after a loop through Point Crescent State Park. The half starts at Sleeper State Park and follows the same coastal stretch in. The 5K is a shorter out-and-back through downtown Port Austin along the same highway. All three courses are paved and flat, and the marathon is Boston-qualifying.
All distances converge on the same finish line in downtown Port Austin. Because the races are point-to-point, shuttles run from the finish area to the marathon start in Caseville before the gun. Parking at Sleeper State Park or Port Austin State Harbor requires a State Recreation Passport, which can be purchased at the gate but costs less if you sort it out ahead of time.
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Finish-Time Stats
Going by the 2025 results, this is a decent-sized field, with a competitive front end and a big recreational middle.
13.1 Miles · 2025 results
377finishers
1:19:16winner
2:08:37median
4:19:06cutoff
Top 3: Joe Robinson (1:19:16) · Parker Austin (1:22:32) · Garrett Jurges (1:24:14)
26.2 Miles · 2025 results
204finishers
2:37:40winner
4:11:05median
6:01:12cutoff
Top 3: Tommy Donohoe (2:37:40) · Austin Fullerton (2:41:08) · Stewart Haadsma (2:41:27)
3.1 Miles · 2025 results
152finishers
19:36winner
35:42median
4:23:32cutoff
Top 3: Nicholas Ochal (19:36) · Lucas Halicki (21:50) · Liam Murphy (21:57)
The Rock CF Thumb Coast Marathon, Half Marathon & 5K has been held every year since at least 2025. That is as far back as RunSignup's records for this race go, so it may well be older.
How we calculate these stats: RunSesh calculates these figures from the most recent published results of past editions, sourced from RunSignup. We show aggregates only: field size, winning and median times, and the cutoff. We never publish individual finisher tables. Last updated Jul 27, 2026.
Distances & Start Times
26.2 Miles11/8/2026 08:00$130
26.2 Miles11/8/2026 08:00$90
13.1 Miles11/8/2026 08:30$100
13.1 Miles11/8/2026 08:30$60
3.1 Miles11/8/2026 09:00$38
5K11/8/2026 09:00$25
26.2 Miles11/8/2026 00:00$50
13.1 Miles11/8/2026 00:00$50
5K11/8/2026 00:00$50
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Where to Stay
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