88th and Colorado, Thornton CO
Sunday, March 29th, 2026
RMRR provides low-cost, low-keyed, supported, and timed training races for runners of all abilities. The races are planned to help you prepare for Boston, Colorado, Colfax, and other long spring races. We make it easy for you to work on your pace, your nutrition and drinking, and getting everything ready for your big race.
Sign up for one, or save money and choose the two race bundle. RMRR members get 50% off.
The races begin at 8am, at the Platte River Trailhead Park, at 88th and Colorado, in Thornton. The courses are out-n-back. so we can accommodate almost any distance between 10-20 miles.
Please note that for everyone's safety, dogs or running strollers are not permitted on our courses. Thanks for understanding.
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