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Fall - Mud Mountain Dam Marathon & Half Marathon

Enumclaw, Washington, United States

calendar_today 19 Sep, 2026

directions_run Running

sell $70.00 – $80.00

About the Event

September 19, 2026 – The Full Marathon Returns!
We’re excited to announce that the Full Marathon is coming back in 2026, and will also be part of our. Start planning now for your next Boston Qualifier on this beautiful, fully paved downhill course, no tunnel, no dirt, no BQ time penalty!

There’s no excuse not to do the dam thing!

Marathon
The marathon course begins at Mud Mountain Dam (elevation 1,400′). Runners will follow a fully paved route through picturesque farmlands and forested areas, tracing the path of the Carbon River. The race finishes in front of the historic McMillin Bridge (elevation 200′), with a total net elevation loss of approximately 1,200′.

Half Marathon
The Half Marathon begins in the scenic town of South Prairie (elevation 467′) and follows a gradual downhill route along the paved Foothills Rail Trail. Runners will enjoy a picturesque journey through farmland and forest, winding alongside the Carbon River and finishing in front of the historic McMillin Bridge (elevation 128′). The course features a net elevation loss of 339 feet.

Races Offered

Fall - Dam Marathon

Sep 19, 2026

straighten

Distance — 26.2 Miles

terrain

Type — Running

timer

07:00

sell

$80.00

Fall - Dam Half Marathon

Sep 19, 2026

straighten

Distance — 13.1 Miles

terrain

Type — Running

timer

08:15

sell

$70.00

Weather History

These values represent the 3-year monthly averages for September in Enumclaw.

thermostat Temperature

10.2° / 20.7°

wb_sunny Feels like

8.8° / 20.0°

light_mode Avg sunshine hours

9h 38m

water_drop Avg rainfall

1.7 mm

ac_unit Avg snowfall

—

air Avg wind speed

5.6 km/h (Light breeze)

opacity Sweat loss rate

Moderate

terrain Course conditions

Firm and slightly soft

sunny Max UV Index

Moderate (3.5)

humidity_mid Humidity

77.5%

wb_twilight Sunrise

06:46

nightlight Sunset

19:18

About Enumclaw

Learn more about the host city, Enumclaw.

Enumclaw is a city in King County, Washington, United States. The population was 12,543 at the 2020 census.

Hotels & Places to Stay

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