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Stone Mill 50 Mile Run

Gaithersburg, United States • 8 Nov 2025

The MCRRC Stone Mill 50 Mile Run is a 50-mile trail ultramarathon in Montgomery Village, Maryland, organized by MCRRC. The course uses forested, rolling terrain along the Seneca Greenway and Muddy Branch trails in Montgomery County, primarily on single-track dirt trails with small stream crossings. Runners should expect well-drained sections but muddy conditions after rain.

Finishing takes place at Stedwick Elementary School in Montgomery Village. The race honors long-time finishers with 5-, 10-, and 15-year milestones, and offers volunteer opportunities and sponsor support. The event emphasizes trail stewardship and features aid stations, spectator tips, and a strong local running club community. Visit the organization's website for the most recent information.

United States Maryland Gaithersburg

Race information

Website Registration
UTMB 50K
50 mi
50 Mile
Visit the organization's website for the most recent information.
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