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Diablo Trail Run

Clayton, United States • 7 Sep 2025

The Diablo Trail Run, held at Diablo State Park in Clayton, California, offers a variety of trail running events including 4-mile, 10-mile, half marathon, marathon, 50K, and a free kids' 50-yard dash for children six and under. The courses feature scenic mountainous terrain with spectacular views of the San Francisco Bay Area. The 4-mile route is relatively flat and fast, while longer distances include significant elevation gains up to 8,000 feet for the 50K.

The trails consist mainly of dirt roads and single-track paths. Aid stations stocked with refreshments are spaced every 3-5 miles. The event emphasizes environmental care by being cupless to reduce waste. Visit the organization's website for the most recent information.

United States California Clayton

Race information

Website
50 km
8000 m+
50k
26 mi
6760 m+
Marathon
13 mi
3420 m+
Half Marathon
10 mi
2420 m+
10 Mi
4 mi
400 m+
4 Mi
Kid's Run (6yo & Younger, 50yd Dash) - Free!
Visit the organization's website for the most recent information.
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