The 2025 event has concluded.

Boulder Rez Marathon

Boulder, CO, USA • August 2, 2025
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rain Clear conditions throughout the day with late afternoon rain.

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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.

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Historical Weather & Results

RunScore
Run Score: 7
Temp
74°F
Min/Max
53°/74°F
Dew
43°F
Days of Rain
0/9
Wind
5mph
Tap a row for details.
YearLow / HighRainResults

Boulder Rez Marathon 2025 Weather History

Clear conditions throughout the day with late afternoon rain.

2025
clear-day
54°/ 90°-
Run Score: 8

Boulder Rez Marathon 2024 Weather History

Clear conditions throughout the day.

2024
clear-day
63°/ 95°-
Run Score: 7

Boulder Rez Marathon 2023 Weather History

Partly cloudy throughout the day.

2023
clear-day
64°/ 82°-
Run Score: 7

Boulder Rez Marathon 2022 Weather History

Partly cloudy throughout the day with late afternoon rain.

2022
clear-day
67°/ 86°-
Run Score: 8

Boulder Rez Marathon 2021 Weather History

Clear conditions throughout the day.

2021
clear-day
61°/ 88°-
Run Score: 7

Boulder Rez Marathon 2019 Weather History

Partly cloudy throughout the day with late afternoon rain.

2019
clear-day
54°/ 74°-
Run Score: 8

Boulder Rez Marathon 2018 Weather History

Partly cloudy throughout the day with late afternoon rain.

2018
partly-cloudy-night
38°/ 45°-
Run Score: 8

Boulder Rez Marathon 2017 Weather History

Clear conditions throughout the day.

2017
clear-night
29°/ 55°-
Run Score: 7

Boulder Rez Marathon 2015 Weather History

Cloudy skies throughout the day.

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

Setting up a racecast.io account will allow you to start building a reputation in the community. Over time you'll be able to rate races, join the discussion, and post in the community.

Right now we are invite only, you can get on the waitlist by entering your email below:

OR
You Need an Account For That

Setting up a racecast.io account will allow you to start building a reputation in the community. Over time you'll be able to rate races, join the discussion, and post in the community.

Right now we are invite only, you can get on the waitlist by entering your email below:

OR