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Boulder Rez Half Marathon

📅 April 10, 2027 (estimated date)📍 Boulder · United States

⚠️ 2027 edition: provisional information

The date is estimated from the 2026 edition (April 11, 2026), on the same day of the week. Courses, start times, fees and description are carried over from the previous edition: check them on the official website. This page will be updated as soon as the organizer publishes them.

Available distances

3.1 mi6.2 mi13.1 mi13.1 mi

About

The Boulder Rez Half Marathon takes place in Boulder, Colorado, in early April, around the Boulder Reservoir. The lineup includes a half marathon (13.1 miles), a half marathon relay, a 10K (6.2 miles) and a 5K (3.1 miles), starting between 8:00 and 8:10 AM. The course follows mostly dirt trails, stays flat and offers views of the mountain range. Distances are accurately measured and clearly marked. The top three men and women overall and the winners of each age group receive awards, and every participant gets a T-shirt and a medal. Boulder sits at a high elevation, so visitors from lower altitudes should allow a day or two to adjust and drink plenty of water.

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