The Alaska Endurance Trail Run (AETR) races offers a distinctive blend of endurance, nature, and community, capturing the adventurous spirit of Alaskan running. Whether you’re chasing mileage goals, training for your next big race, or simply seeking a fun challenge in the land of the midnight sun, AETR is a true celebration of human endurance in the Far North.

The Alaska Endurance Trail Run is a grassroots, community-driven ultramarathon event held annually in Fairbanks, Alaska. Founded and directed by Don Kiely, AETR is a timed-format race where participants aim to cover as much distance as possible within a set time frame of 6, 12, or 24 hours. Since its inaugural year in 2015 (with a brief COVID-related cancellation in 2020), the event has grown into a beloved endurance challenge in Interior Alaska.

Taking place on the mildly hilly trails of the University of Alaska Fairbanks (UAF) West Ridge, the race offers a 6+ mile loop that is both accessible and demanding—designed to test the stamina of runners and walkers alike without requiring technical trail experience. With multiple start times spread across Friday night and Saturday, participants can tailor their experience and choose to race through the midnight sun or in broad daylight.