Carkeek 12 Hour

Endless Trails’ Carkeek 12-Hour returns for its 19th edition at Carkeek Park in Seattle, Washington, offering in-person and virtual options. Runners choose between a 12-hour or 6-hour race, looping a 1.93-mile course with about 436 feet of elevation gain per lap, featuring rolling trails, stairs, and Puget Sound views. The atmosphere blends hardcore endurance with Halloween fun—costumes are encouraged, pets are welcome, and prizes are awarded for standout outfits.

Proceeds benefit Endless Trails, with a cap of about 50 participants to keep the event cozy. The day is low-tech and community-driven, with a spirited loop-based crowd. Visit the organization's website for the most recent information.