Beat the Sunset in Caseville, Michigan!

Michigan’s Thumb is full of quiet roads, big skies, and unexpected beauty—and the 2027 Thumb Coast Ultra & Relay is your chance to run from one side of Lake Huron to the other.

On Saturday, April 24, take on a point-to-point 50 Mile from Lake Huron in Harbor Beach to Saginaw Bay in Caseville, a fast and scenic 50K out-and-back, or rally your crew for the 50 Mile Relay and chase the sun across the Thumb. Can you beat sunset to the finish?

This route follows mostly flat dirt roads through open farmland and lakeshore views, with generous cutoff times and fully stocked aid stations. It’s an ideal challenge for beginners going long for the first time, seasoned vets chasing a PR, or teams ready to take on 50 miles together. Whether you’re running, rucking, or relaying—this is your spring adventure.

Additional awards for 50 Mile finishers who “beat the sun.”
Let’s go coast to coast—Thumb-style.

50 Mile & 50 Mile Relay Course

The 50 Mile course is point-to-point, starting at sunrise in Harbor Beach, Michigan and finishing on the beach at Caseville County Park.  The course consists of ~85% dirt roads, 10% paved roads, and 5% unimproved park roads (think gnarlier and sandier than dirt roads).  With ~500' elevation gain it's a gorgeous, fast course!

The course is open ~15 hours, give or take 10 minutes for sunrise/sunset.

Learn more and view the course on Strava:

50K Course

The 50K course is an out-and-back course, starting and finishing on the beach at Caseville County Park.  This course uses mostly unimproved and gravel roads.  With ~220' of elevation gain it's a fun, fast race!

The course is open ~13 hours, give or take 10 minutes for sunrise/sunset.

Learn more and view the course on Strava:

What's Included in Registration?

• Custom Thumb Coast Ultra participant jacket*

• Thumb Coast Ultra bumper sticker

• Reusable 8 oz silicone race cup

• Finisher's medal

• Race photography

• Post race food and drinks

  • In addition to traditional post race snacks Trivium will serve hot dogs and burgers hot off the grill.

• Aid stations well-stocked with water, Tailwind, gels, and real food

*2027 design and style will be announced soon and could change from a jacket to a sweatshirt.

Race Weekend Schedule

Friday, April 23, 2027:  Early Packet Pickup

Thumb Brewery

6758 Pine St, Caseville, MI 48725

2-7 pm*

Saturday, April 24, 2027: Race Day

• 50 Mile Ultra & Relay start: 6:27 am EST in Harbor Beach, MI (Sunrise)
• 50K start: 8:30 AM in Caseville, MI
• 50 Mile cutoff for the special "I Beat the Sun" Award:  8:29 pm EST Caseville, MI (sunset)
• 50 Mile and 50K courses close: 9:30 pm EST

*Packet pickup time subject to change.

Join Our Volunteer Crew

Not racing but still want to be part of the adventure?

Join the crew that makes it all happen—become a volunteer at the 4th Annual Thumb Coast Ultra & Relay!

Click below to learn more, sign up, and be an essential part of the action.

Start & Finish Line Locations

Click the links below for Google map locations for the start/finish lines.

Start Line for 50 Mile: Harbor Beach

Start/Finish Line for 50K and 50 Mile Finish Line:  Caseville County Park

Official Training TWB Plans

Official Thumb Coast Ultra & Relay training plans are $35 for Ultramarathon plans (20 weeks in length) and $25 for Relay plans (12 weeks in length).  All plans are designed by Team Wicked Bonkproof (TWB)'s Coach Caleb & team.  Learn more at the link below.

Join our community online year round:

Facebook:  Thumb Coast Ultra & Relay

Instagram:  @thumbcoastultra

What Past Participants are Saying

The social proof is in the referrals!

Finisher's Medal

2027 design coming soon.

Participant Jacket

2027 design and style coming soon.