Rosaryville Half Marathon

Upper Marlboro, United States • 28 Mar 2026

Event Overview

The Rosaryville Half Marathon is a trail running event offering three distances: half marathon, 10K, and 5K. It takes place at Rosaryville State Park in Upper Marlboro, Maryland.

Course Details

The course is located within Rosaryville State Park, convenient to the Capital Beltway. It winds through mixed hardwood forests and fields on trails described as twisty, relatively smooth, flat, and fast. The course is not considered overly technical.

The half marathon covers ~13.5 miles with an elevation gain of about 1,000 feet. It uses the 9-mile perimeter trail, the 2-mile interior trail, and wide horse trails. The 10K+ course is ~6.7 miles with ~500 feet of gain, combining 5 miles of the perimeter trail with over a mile of horse trails. The 5K+ course is ~3.6 miles with ~250 feet of gain, using part of the perimeter trail and some equestrian trails.

Aid Stations & Amenities

Aid stations are provided along each course. There are nine on the half marathon route, four on the 10K route, and two on the 5K route. All stations supply cups, water, and Gatorade. One station on the half marathon route also offers snacks.

Registration includes a finisher medal, a race t-shirt, professional race operations, volunteer support, medical support, post-race food, free race photos, and awards. Visit the organization's website for the most recent information.

Race information

Half Marathon
Half Marathon
10 km
10k
5 km
Visit the organization's website for the most recent information.
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