Tunnel Light Marathon
Tunnel Light Marathon descends from the Snoqualmie Tunnel onto the Palouse to Cascades Trail, creating a fast September Boston qualifying course.
Every link above goes to the race, its timing provider, or an official registration partner. Last checked July 21, 2026.
Quick facts
- Net-downhill Washington Boston qualifier
- Run through the Snoqualmie Tunnel
- September edition of the Tunnel Marathons
- Rail-trail course toward North Bend
About the Tunnel Light Marathon
Tunnel Light is the September race in Washington's three-edition Tunnel Marathons series. Its own date and registration distinguish it from the June and August events, despite the shared course family.
Course
After the dark, cool Snoqualmie Tunnel, runners follow a net-downhill rail trail toward North Bend. A headlamp is essential underground, and sustained gentle descent rewards restrained early pacing.
Race-day weather
Mountain air at the start may be cool and damp while the lower finish turns warmer. Tunnel moisture, trail dust, sun and changing temperatures can all appear in one race.
Past Tunnel Light Marathon dates and results
| Year | Date | Status | Results |
|---|---|---|---|
| 2026 | Sunday, September 13, 2026 | Upcoming | — |
Tunnel Light Marathon FAQ
When is the Tunnel Light Marathon?
The 2026 Tunnel Light Marathon is on Sunday, September 13, 2026.
How do I register for the Tunnel Light Marathon?
You can register for the Tunnel Light Marathon at ultrasignup.com.
Can I use the Tunnel Light Marathon for Boston qualifying?
Marathon Scout marks the Tunnel Light Marathon as a Boston qualifier. Check the current Boston qualifying times and confirm current certification with the race before registering.
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