In 3 days, several thousand runners will head onto the snow-covered slopes of Mount Hood in Oregon. Timberline Marathon is one of the Pacific Northwest's most iconic trail races — a marathon and half marathon on volcanic alpine terrain, with glacier views and real snow in the middle of June.
Key Info
- Timberline Marathon and Half: June 6-7, 2026, Mount Hood, Oregon
- Terrain: volcanic, above treeline, significant residual snow
- Elevation: course climbs to 8,500+ feet (2,600m)
- Hub: the historic 1937 WPA Timberline Lodge at 6,000 feet
Why run on a volcano in June
Mount Hood is Oregon's tallest volcano (11,249 feet at the summit) and one of the most active in the Cascade Range. In June, snow still covers most of the mountain above 5,500-6,000 feet — giving Timberline its unique texture: a summer trail run partly on snowpack, with temperatures ranging from 40°F to 70°F depending on time and elevation.
The Timberline Lodge — built by the WPA in 1937 and used as the exterior for Kubrick's The Shining — serves as the race start and finish. It's a detail that doesn't escape runners who value races with history and a setting beyond a standard circuit.
Running in altitude: what to expect
Altitude is the factor non-acclimatized runners consistently underestimate. At 8,500 feet, partial oxygen pressure is roughly 25% lower than sea level. In practice: an effort that feels "moderate" at sea level is physiologically harder at altitude. Key adjustments: reduce target pace by 10-15%, increase fluid intake (altitude accelerates dehydration), and don't try to "make up" the pace difference by pushing harder.
For runners not acclimatized: arriving 2-3 days before the race at altitude provides partial adaptation. Full acclimatization takes 3-6 weeks — for a race like this, partial adaptation already helps significantly.
Key takeaways
- Timberline Marathon: June 6-7, Mount Hood — volcanic snowy terrain, elevation up to 8,500 feet.
- Reduce pace targets by 10-15% vs your normal altitude results.
- Increase hydration: dry cold air at altitude accelerates insensible water losses.
- Layer up: Mount Hood June weather is unpredictable (wind, rain, sunshine can all happen in one morning).