About This Race
The Stone Mill 50 Miles offers runners a quintessential Maryland trail experience through Montgomery County's forested terrain. This challenging ultra marathon combines the scenic Seneca Greenway and Muddy Branch trails in a course that showcases the region's natural beauty while demanding respect for its technical sections. The route features primarily single-track dirt trails with rolling topography and multiple small stream crossings that add both charm and challenge to the experience. Parts of the course can become muddy in wet weather, though most sections drain well, creating conditions that vary significantly with the season and recent precipitation.
The course traverses 50 miles of forested, rolling terrain on primarily single-track dirt trails through Montgomery County's trail network. Runners will encounter multiple small stream crossings and experience the natural drainage patterns of the region, with some sections prone to muddiness during wet conditions. The route combines the scenic Seneca Greenway and Muddy Branch trails, offering a technical challenge with 3,839 feet of elevation gain spread across the undulating Maryland landscape.
Aid Stations
10 stations along the course
Aid Station 1
Aid Station 2
Aid Station 3
Aid Station 4
Aid Station 5
Aid Station 6
Aid Station 7
Aid Station 8
Aid Station 9
Aid Station 10
Practical Info
November in Maryland typically brings cool temperatures with potential for rain, creating variable trail conditions from dry and fast to muddy and technical.
DCA - Ronald Reagan Washington National Airport
Montgomery Village area provides various lodging options, with additional accommodations available in nearby Rockville and the greater Washington D.C. metropolitan area.
Best For
Notable Features
This race stands out for its commitment to trail stewardship and community involvement, requiring participants to volunteer six hours with local running organizations before race day. The November timing provides cooler running conditions while potentially adding weather variability. The course showcases two distinct trail systems in Montgomery County, creating a diverse running experience through Maryland's well-maintained trail network.