United States·2026

Boulder, CO

Boulder's running and cycling culture revolves around elevation and altitude training — the city sits at 1,655 metres with trails climbing into the Flatirons and Rocky Mountain foothills immediately west. Runners dominate the trails around Bear Canyon and Flagstaff Mountain (1,951m top), while cyclists tackle the Valmont Short Track Series for road racing and venture north to the Buffalo Bicycle Classic's rolling terrain or west toward the high passes of The Triple Bypass. The combination of thin air, relentless climbing, and year-round conditions makes Boulder a base for serious endurance athletes.