Colorado Triathlon

Recently named a Top 10 Race in America by USA Today and one of the Best Fall Marathons by Runner’s World, Boulderthon® is Colorado’s premier fall race and one of the fastest-growing marathons in the country. This event offers five distinct race options, including the Marathon, Half Marathon, 10K presented by Cheribundi, the Heart to Heart 5K by BCH, and the Kids Run, making it a perfect event for runners of all abilities. The marathon and half marathon courses feature sweeping views of the Flatirons, Boulder Reservoir, Table Mountain, and Haystack Mountain, before the unforgettable downtown finish on Pearl Street. The 10K takes runners through Boulder’s scenic streets, also ending on Pearl Street, while the Heart to Heart 5K, known for its $40,000 prize purse, is one of the largest 5K purses in the nation.

Boulder, Colorado, offers a stunning backdrop for the race, with crisp fall air and golden leaves surrounding the runners as they race through the city. After the race, explore Pearl Street and its vibrant shops, or take in the nearby outdoor attractions like Chautauqua Park or the Flatirons. With its combination of big-race energy and small-town charm, Boulder is the perfect location to both race and unwind.

Scenic Views – Experience sweeping vistas of the Flatirons, Boulder Reservoir, and Table Mountain during the race.

Multiple Distances – With five race options, including a $40,000 prize 5K, there’s something for everyone from first-timers to seasoned marathoners.

Pearl Street Finish – Cross the iconic Pearl Street finish line, surrounded by cheers and excitement, in the heart of Boulder’s vibrant downtown.