RMRR December 4.5mi

RMRR December 4.5mi is held in Denver, Colorado, on December 6, 2026, at Washington Park. The race covers 4.5 miles (about 7.2 km) with a 9:00 AM start and is part of the RMRR Trophy Series. The distance sits between a 5K and a 10K, which makes it a good measuring stick for your winter fitness without the recovery demands of a longer race.

If you have been racing 5Ks this fall, 4.5 miles asks for a slightly more controlled effort: start a touch slower than 5K pace and aim to hold it evenly. Runners building toward a spring 10K or half marathon can use the race as a tempo-effort checkpoint, with an easy week before it and normal training resuming a couple of days later. Keep in mind Denver's altitude and December temperatures, so warm up properly, wear layers you can remove, and do not be surprised if your pace is a little slower than at sea level.