October ultramarathons in Maryland, United States

Multiple loops on a 5.22-mile single-track course with 750 feet of elevation gain per lap, starting and finishing by Greenbrier Lake's sandy shore

Three-loop 50K featuring rugged singletrack climbs, ridge traverses, gorge views, tranquil lake stretches, and 2,600 feet of elevation gain in Rocky Gap State  

Dirt singletrack and rolling hills through Patapsco Valley State Park, with creek crossings, muddy sections, and some paved stretches near Baltimore