Colorado Runner

BOLDERBoulder: Third-Largest U.S. Race in 2025; Largest 10K

Jan 24, 2026 12

Jan 23, 2026 404

Jan 22, 2026 11

For a full list of race results, click here.

Donut Dash

5K
April 12, 2026
Washington Park | Denver, CO
2026 RRCA Colorado 5K Championship

Greenland Trail Races

50K, 25K, 8M and 4M
May 2, 2026
Greenland Open Space | Larkspur, CO
2026 RRCA National 50K Championship

Flamingo Day 5K

5K
June 7, 2026
Sloan’s Lake Park | Denver, CO

Cookie Chase

5K
July 11, 2026
Sloan’s Lake Park | Denver, CO

Labor Day Half Marathon

Half Marathon, 10K and 5K
September 7, 2026
Salisbury Park | Parker, CO

Ghosts & Goblins 5K

5K and 10K
October 25, 2026
City Park | Denver, CO

Pumpkin Pie 5K

5K and 10K
November 21, 2026
City Park | Denver, CO

Ugly Sweater 5K

5K
December 20, 2026
Washington Park | Denver, CO