The 2025 event has concluded.

Boulder Rez Marathon

Boulder, CO, USA • August 2, 2025
TopDescriptionCourse

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rain Clear conditions throughout the day with late afternoon rain.

This amazing run course will take you alongside the Boulder Reservoir, remaining mostly on dirt roads and trails. The course is flat with only 200 feet of gain, and will provide views of the Boulder Reservoir and Rocky Mountains. Source

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When is the 2025 Boulder Rez Marathon?

The 2025 Boulder Rez Marathon will be held on Saturday August 2, 2025.

Is the Boulder Rez Marathon a Boston Marathon Qualfier?

Yes, the Boulder Rez Marathon is an official Boston Marathon qualifier.

Historical Weather

Based on 9 years of data
Avg Temp
74°F
L:53°H:74°
RunScore
7
Conditions
Rain Freq
0%
0 of 9 yrs
Wind5mph
Dew43°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScoreResults

2025 Boulder Rez Marathon

Clear conditions throughout the day with late afternoon rain.

2025
clear-day
54°/90°-
8

2024 Boulder Rez Marathon

Clear conditions throughout the day.

2024
clear-day
63°/95°-
7

2023 Boulder Rez Marathon

Partly cloudy throughout the day.

2023
clear-day
64°/82°-
7

2022 Boulder Rez Marathon

Partly cloudy throughout the day with late afternoon rain.

2022
clear-day
67°/86°-
8

2021 Boulder Rez Marathon

Clear conditions throughout the day.

2021
clear-day
61°/88°-
7

2019 Boulder Rez Marathon

Partly cloudy throughout the day with late afternoon rain.

2019
clear-day
54°/74°-
8

2018 Boulder Rez Marathon

Partly cloudy throughout the day with late afternoon rain.

2018
partly-cloudy-night
38°/45°-
8

2017 Boulder Rez Marathon

Clear conditions throughout the day.

2017
clear-night
29°/55°-
7

2015 Boulder Rez Marathon

Cloudy skies throughout the day.

2015
cloudy
47°/54°-
8
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You Need an Account For That

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