Mines Of Spain 100 - Dubuque, IA

Dubuque, United States • 17-18 Oct 2025

The Mines of Spain 100 is a challenging Midwest trail ultramarathon held in Dubuque, Iowa, set in the scenic bluffs, prairies, and forests of the Driftless Region along the Mississippi River valley. The event offers two distances: 100 miles (five loops) and 100 kilometers (three loops) on a roughly 20-mile course featuring diverse terrain including steep technical single track, rolling dirt and prairie double track, and some paved connectors. Runners experience stunning views of the Mississippi River, Horseshoe Bluff, grass prairies, and hardwood forests. The race emphasizes a grassroots, well-organized atmosphere supporting local trail maintenance, welcoming both first-time and veteran ultrarunners. Visit the organization's website for the most recent information.

Race information

100 mi
100 Mile
100 km
100 Kilometer
Visit the organization's website for the most recent information.
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