Cirque Series - Arapahoe Basin

Cirque Series - Arapahoe Basin

Cirque Series - Arapahoe Basin is a mountain trail race held at Arapahoe Basin, Colorado on Sept 5, 2026. The course covers 9.4 miles with 2,211 ft vert and begins at 10,780 ft at Mountain Goat Plaza. The route follows roads and established trails in the White River National Forest and is subject to change as necessary.

The course climbs from the base of Arapahoe Basin up the A-Basin summer road past Black Mountain Lodge, connects to a new singletrack near the top of the Pali lift and continues toward Zuma Cornice. Runners cross service roads to the top of the Montezuma Lift, follow the Lenawee trail and summit Little Lenawee peak before returning. The descent uses the Half Moon Vista high alpine trail and the Argentine North Fork singletrack through shaded forest, finishing on a mountain bike singletrack into Mountain Goat Plaza where live music and food are provided.

Safety protocols are emphasized; the course is steep and technical in sections, especially on Little Lenawee summit area, and flagging must be followed. Competitors are subject to a strict cutoff at Black Mountain Lodge Aid Station #1 of 30 minutes. The race field is capped at 700 runners. Each competitor receives a snapback, giveaway ticket, logoed bib and medal, a sponsor swag bag and free professional photos. Visit the organization's website for the most recent information.