Alaska is known for testing human endurance in sports.

This weekend is no exception, as the annual Alaskaman Extreme Triathlon starts Saturday morning in Seward.

Athletes will start with a 2.6 mile swim. That's followed by a 113-mile bike ride to Girdwood, before racers finish with a 26-mile run to the Alyeska Resort.

Alaskaman's race director, Aaron Palaian, calls the grueling race the nation's single most challenging extreme triathlon.

"I think the untamed beauty and the pureness of the sport here is different than other places," Palaian said. "I've been a lot of places around the country that do triathlons. I think there is a time and a place for everything; some of them are not about the course or nature, but it's about speed and competition. Here, the athletes can connect with nature and that wild side, and challenge against themselves."

Alaskaman starts at Miller's Landing in Seward at 4:45 a.m. Saturday.

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