Race Start End City State
HRCA Oktoberfest 5K Sep. 26, '26 Sep. 26, '26 Littleton CO REGISTER
Beulah Challenge and OverIt Series Sep. 19, '26 Sep. 19, '26 Beulah CO REGISTER
Golden Harvest Half Marathon & 5k/10k - Denver Sep. 5, '26 Sep. 5, '26 Denver CO REGISTER
Oak Creek No Fun Run Sep. 7, '26 Sep. 7, '26 Oak Creek CO REGISTER
Run for Mental Health 5K/10K/13.1 DENVER/AURORA Sep. 12, '26 Sep. 12, '26 Centennial CO REGISTER
Demon Dash Sep. 5, '26 Sep. 5, '26 Arvada CO REGISTER
6 Dot Dash Sep. 12, '26 Sep. 12, '26 Littleton CO REGISTER
Labor Day Half Marathon Sep. 7, '26 Sep. 7, '26 Parker CO REGISTER
Oktoberfest Run 5K/10K/13.1 DENVER/AURORA Sep. 26, '26 Sep. 26, '26 Centennial CO REGISTER
Tiger Prowl 5K Sep. 13, '26 Sep. 13, '26 Denver CO REGISTER
Joy & Justice 5k Sep. 27, '26 Sep. 27, '26 Timnath CO REGISTER
Parker Parks and Recreation So Long to Summer 5K/10K Sep. 26, '26 Sep. 26, '26 Parker CO REGISTER
20th Annual Golden Gallop Sep. 20, '26 Sep. 20, '26 Golden CO REGISTER
All-Out Fall Fest Sep. 19, '26 Sep. 19, '26 Westminster CO REGISTER
For The City Network 5K Sep. 12, '26 Sep. 12, '26 Greeley CO REGISTER
Wellington STAR Foundation 5K 10K Sep. 19, '26 Sep. 19, '26 Wellington CO REGISTER
South Fork Alder Ass Race Sep. 5, '26 Sep. 5, '26 South Fork CO REGISTER
Spirit of the Valley 5k Sep. 12, '26 Sep. 12, '26 Grand Junction CO REGISTER
Golden Harvest Half Marathon & 5k/10k - Colorado Springs Sep. 6, '26 Sep. 6, '26 Colorado Springs CO REGISTER
Autumn Run Sep. 19, '26 Sep. 19, '26 Buena Vista CO REGISTER
Miles 4 Madison 5K & 1K Sep. 19, '26 Sep. 19, '26 Littleton CO REGISTER
All Hands on Deck The Pirates 5K Sep. 19, '26 Sep. 19, '26 Colorado Springs CO REGISTER
Runway 5K - Run for the Angels Sep. 26, '26 Oct. 3, '26 Broomfield CO REGISTER
Severance Glow 5K Run or Walk Sep. 18, '26 Sep. 18, '26 Severance CO REGISTER
National Chocolate Day: Run for Chocolates 5K/10K/13.1 DENVER/AURORA Sep. 12, '26 Sep. 12, '26 Centennial CO REGISTER
Break Your Neck: Walk, Run, or Roll Sep. 12, '26 Sep. 12, '26 Pueblo CO REGISTER
Farmers 5000 Sep. 20, '26 Sep. 20, '26 Wheat Ridge CO REGISTER
2026 Center of the Nation Series - Day 2 (CO) Sep. 29, '26 Sep. 30, '26 Sterling CO  
McGinn Memorial Cross Country Challenge Sep. 26, '26 Sep. 26, '26 Pagosa Springs CO REGISTER
Boggy Draw Bear Chase Sep. 25, '26 Sep. 25, '26 Dolores CO REGISTER