Running Events in Boulder

Check out happening running events all around Boulder, CO

Colorado Triathlon (Sprint, Olympic, Duathlon, & Aquabike)

 Sat, 06 Jun at 07:15 am Boulder Reservoir

Boulder Rez Half Marathon

 Sat, 11 Apr at 08:00 am Boulder Reservoir

Chelsea Sodaro: An Unlikely Journey to Triathlon, Motherhood, and Ironman World Champion

 Wed, 18 Mar at 07:30 pm Chautauqua Community House

Lucky Leprechaun 5K

 Sat, 14 Mar at 04:00 pm Twisted Pine Brewing

2026 Boulder Polar Plunge presented by Spectrum

 Sat, 04 Apr at 11:00 am Boulder Reservoir

Harvest Moon Long Course Triathlon

 Sun, 31 May at 07:15 am Boulder Reservoir

2026 Full Moon Challenge 12K and 12M

 Sat, 07 Feb at 01:00 pm Boulder USD 4 to 42

2026 World Cancer Day 1M 5K 10K 13.1 26.2

 Sun, 01 Feb at 01:00 pm Boulder USD 4 to 42