Spring - Mud Mountain Dam Marathon & Half Marathon
Typically 42–59°F · some rain risk
See last 10 years
On this date: rain 4 of the last 10 years
2026
42–52°F
rain
2025
43–57°F
rain
2024
38–46°F
rain
2023
45–62°F
dry
2022
38–43°F
rain
2021
36–63°F
dry
2020
55–70°F
dry
2019
47–62°F
dry
2018
40–50°F
dry
2017
51–74°F
dry
Best months to race in Washington →
About this race
Start Planning Now for Your Next Boston Qualifier!
Take on a beautiful, fully paved downhill course with no tunnel, no dirt, and no BQ downhill penalty.
Full Marathon
The Marathon starts at Mud Mountain Dam, high above the Carbon River at an elevation of approximately 1,400 feet.
From there, runners will follow a fully paved downhill route through picturesque farmland and forest, tracing the scenic Carbon River before finishing at the McMillin Farm Collective at approximately 128 feet.
That's a net elevation loss of about 1,200 feet—a fast, scenic course built for a memorable Boston Qualifier!
Half Marathon
The Half Marathon starts in the scenic town of South Prairie at approximately 467 feet and follows a gradual downhill route along the paved Foothills Rail Trail.
Runners will wind through farmland and forest alongside the Carbon River before finishing at the McMillin Farm Collective, at approximately 128 feet.
The course features a net elevation loss of 339 feet.
A Finish Line Worth Celebrating!
We've got a brand-new finish line just down the road from the McMillin Bridge, and we're making it a destination!
After crossing the finish line, stick around and celebrate with:
Brewhouse
Food trucks
Hot & Cold plunge pools
It's going to be a finish line to remember!
Beautiful course. Fast downhill miles. Fully paved. No tunnel. No dirt. No BQ penalty.
There’s no excuse not to do the dam thing!
Course map
Train with a club
Run clubs near Enumclaw to train with before race day.
Suggested Races
Organize this race?
Claim it free to manage your listing. Want it first in every search? Boost it for $1 a day.