Course
Marathon42.2 km
3/4 Marathon30.4 km
Half Marathon21.1 km
10K10 km
Key dates
- ·RegistrationNot open yet
- ★Race dayAugust 2027 · date to be announced
Provisional date, projected from last year — the organiser has not announced this edition yet. We show the month only.
About
This USATF-sanctioned race circles Boulder Reservoir on dirt roads and trails, with views of the Rocky Mountains and only about 200 feet of climb over the full marathon. Distances range from 10K up to a full marathon, plus a marathon relay option.
Your next race, seen from above.
Save Boulder Rez Marathon to your season and RunCalendar reminds you the morning entries open and before they close. Free on iPhone, no account needed.
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Save Boulder Rez Marathon to your season and RunCalendar reminds you the morning entries open and before they close. Free on iPhone, no account needed.
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A confirmed date shows its day; a provisional one shows only its month, because we won't claim a day we don't have. This page is rebuilt every night from the RunCalendar catalogue.