Upcoming Races Near Boulder, CO in May, 2026

Name: Weld Your Mettle Running Festival
Start: 2026-05-30
End: 2026-05-30
Location: Eaton

Friends of the National Center Science Stride 5K

Boulder, CO

Friday, May 1st, 2026

Featured

View details for race Friends of the National Center Science Stride 5K

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Adams County Foster Care 5K Run/Walk and 1 mile...

Brighton, CO

Saturday, May 2nd, 2026

1 Mile

View details for race Adams County Foster Care 5K Run/Walk and 1 mile fun run

9th edition CollaBEERation 5k & Brew Fest Party

Longmont, CO

Saturday, May 2nd, 2026

View details for race 9th edition CollaBEERation 5k & Brew Fest Party

22nd Annual Bob Turner Classic 5K Run/Walk

Berthoud, CO

Saturday, May 2nd, 2026

View details for race 22nd Annual Bob Turner Classic 5K Run/Walk

High Line Canal 5K/10K Run

Centennial, CO

Saturday, May 2nd, 2026

10K

View details for race High Line Canal 5K/10K Run

The Colorado Marathon

Fort Collins, CO

Sunday, May 3rd, 2026

Marathon

Half

10K

View details for race The Colorado Marathon

Frank Shorter Track Classic

Longmont, CO

Sunday, May 3rd, 2026

1 Mile

View details for race Frank Shorter Track Classic

Rise Against Suicide - Emerge 5K

Boulder, CO

Sunday, May 3rd, 2026

View details for race Rise Against Suicide - Emerge 5K

2026 Altitude Elementary Moose Mudder

Aurora, CO

Sunday, May 3rd, 2026

View details for race 2026 Altitude Elementary Moose Mudder

RMRR May Trophy Series

Denver, CO

Sunday, May 3rd, 2026

Fast

View details for race RMRR May Trophy Series

Longmont Half & 5k (LM Half)

Longmont, CO

Sunday, May 3rd, 2026

Half

View details for race Longmont Half & 5k (LM Half)

Dash & Dine 5k #2

Boulder, CO

Tuesday, May 5th, 2026

View details for race Dash & Dine 5k #2

Parker Parks and Recreation Miles over the Mead...

Parker, CO

Saturday, May 9th, 2026

1 Mile

View details for race Parker Parks and Recreation Miles over the Meadow Mother’s Day 5K & Family Fun Trek

Run For The Trees - 2 Mile Fun Run

Loveland, CO

Saturday, May 9th, 2026

View details for race Run For The Trees - 2 Mile Fun Run

Cherry Creek Race for the Watershed 2026

Aurora, CO

Saturday, May 9th, 2026

View details for race Cherry Creek Race for the Watershed 2026

2026 Five Star 5K, Mile of Smiles, and Wellness...

Brighton, CO

Saturday, May 9th, 2026

1 Mile

View details for race 2026 Five Star 5K, Mile of Smiles, and Wellness Festival

Quad Rock 25 & 50 Mile Trail Races

Bellvue, CO

Saturday, May 9th, 2026

Ultra

Trail

View details for race Quad Rock 25 & 50 Mile Trail Races

HRCA Mother's Day 5K

Highlands Ranch, CO

Saturday, May 9th, 2026

View details for race HRCA Mother's Day 5K

Colorado Women's Classic - Westminster

Westminster, CO

Sunday, May 10th, 2026

10K

10 Miles

View details for race Colorado Women's Classic - Westminster

Denver Mother's Day 5K

Denver, CO

Sunday, May 10th, 2026

View details for race Denver Mother's Day 5K

Hometown Half Marathon & 5k/10k - Denver

Denver, CO

Sunday, May 10th, 2026

10K

Half

View details for race Hometown Half Marathon & 5k/10k - Denver

Gluten Free Gallop 5K

Littleton, CO

Saturday, May 16th, 2026

View details for race Gluten Free Gallop 5K

Healing Warriors Program 2026 Annual 5K Fun Run

Fort Collins, CO

Sunday, May 17th, 2026

View details for race Healing Warriors Program 2026 Annual 5K Fun Run

Girls on the Run Rockies Colfax SoleMates 2026

Denver, CO

Sunday, May 17th, 2026

Marathon

Half

View details for race Girls on the Run Rockies Colfax SoleMates 2026

Miles for Smiles 5K

Arvada, CO

Sunday, May 17th, 2026

Trail

View details for race Miles for Smiles 5K

AdventHealth Race to Rebuild

Lone Tree, CO

Wednesday, May 20th, 2026

1 Mile

View details for race AdventHealth Race to Rebuild

Weld Your Mettle Running Festival

Eaton, CO

Saturday, May 30th, 2026

Ultra

Marathon

View details for race Weld Your Mettle Running Festival

Explore more in Boulder, CO

Distances:

5K 10K Half Marathon Marathon

Months:

March April May

Tags:

Trail Boston Qualifiers Fast Courses

State:

All Colorado races

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