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Races in Colorado 2026–2027

There are 7 upcoming races in Colorado on the 42Cal calendar, from September 2026 through June 2027.

7
Upcoming races
September 2026 – June 2027
Date range
1
Countries
603 ft
Median elevation

Race data last updated .

Upcoming Races in Colorado 2026–2027

  1. Sep 27, 2026
    Registration Open

    Boulderthon

    Boulder, Colorado, United States
    Marathon

    Also: Half Marathon, 10K, 5K

    See full guide
  2. Oct 4, 2026
    Registration Open

    Hot Chocolate 15K/5K Denver

    Denver, Colorado, United States
    Other

    Also: 5K, 10K

    See full guide
  3. Apr 18, 2027
    Registration Open

    Horsetooth Half Marathon

    Fort Collins, CO, United States
    Half Marathon
    See full guide
  4. May 2, 2027
    Opening Soon

    Colorado Marathon

    Fort Collins, CO, United States
    Marathon

    Also: 5K, 10K, Half Marathon

    See full guide
  5. May 16, 2027
    Opening Soon

    Colfax Marathon

    Denver, CO, United States
    Marathon

    Also: Half Marathon, 5K

    See full guide
  6. May 31, 2027
    Registration Open

    BolderBOULDER

    Boulder, Colorado, United States
    10K
    See full guide
  7. Jun 6, 2027
    Opening Soon

    Steamboat Marathon

    Steamboat Springs, Colorado, United States
    Marathon

    Also: Half Marathon, 10K

    See full guide

Compare These Races

RaceDateLocationDistanceElevationStatus
BoulderthonSeptember 2026Boulder, United StatesMarathon603 ftRegistration Open
Hot Chocolate 15K/5K DenverOctober 2026Denver, United StatesOther30 mRegistration Open
Horsetooth Half MarathonApril 2027Fort Collins, United StatesHalf Marathon280 mRegistration Open
Colorado MarathonMay 2027Fort Collins, United StatesMarathon180 mOpening Soon
Colfax MarathonMay 2027Denver, United StatesMarathon211 mOpening Soon
BolderBOULDERMay 2027Boulder, United States10K400 ftRegistration Open
Steamboat MarathonJune 2027Steamboat Springs, United StatesMarathon736 ftOpening Soon

Related Collections

Half Marathons in ColoradoHalf Marathons in CaliforniaHalf Marathons in FloridaHalf Marathons in GeorgiaHalf Marathons in MichiganHalf Marathons in Minnesota

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