Carkeek 12 Hour

The Carkeek 12-Hour is a challenging trail running event held annually at Carkeek Park in Seattle, Washington. Celebrating its 19th edition in 2025, the race offers both 12-hour and 6-hour options on a 1.93-mile loop course featuring 436 feet of elevation gain per lap, including rolling trails and steep stairs with scenic views of Puget Sound. Known as one of the toughest 12-hour races, it embraces a fun, festive atmosphere with encouraged Halloween costumes, prizes, and support for costumed pets.

The event supports local trails through Endless Trails, a nonprofit, and limits participation to 50 runners to maintain a cozy, old-school vibe. Virtual participation is also available. Visit the organization's website for the most recent information.