Boulder Rez Marathon

Race Date

Aug 15, 2026

Location

Boulder, CO

Logistics

Race Day

Saturday, August 15, 2026

Start Time

TBA

Start Location

Boulder, CO

Directions

Course Info

USATF Certified

Course Type

Loop Course

Terrain

road

Difficulty

Ultra-Flat

Net Drop/km

0 m (Flat)

Separation

0.0%

Also Offers

26.2M19.7M10K run | 26.2M relay

USATF Certified Course

CO25001MWC · Expires 2035 · Boulder Reservoir Half Marathon

Relatively flat with minimal net elevation change. Loop course — start and finish are close together.

View USATF Course Map (PDF)

Historical Performance

Median Finish

2:12:32

10:07/mi

Winning Time

1:22:38

6:18/mi

Finishers (2025)

194

States Represented

6 / 50

Gender Split

61% Female39% Male

Finish Time Distribution

1:205:30

FASTER 25%

1:58:38

MEDIAN

2:12:32

SLOWER 25%

2:35:39

Average runner age: 33

See Full Results

Race Day Weather

5-year historical avg

Start (Low)

58°

Afternoon (High)

85°

Hot conditions — adjust pace expectations, prioritize hydration

0.0"

Precipitation

9 mph

Wind

48%

Humidity

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