The Rick O'Donnell 5.22 Mile Trail Run and 8-hour Ultra Challenge, held in beautiful Greenbrier State Park, Boonsboro, MD, is ideal for your first trail race, timed event or ultra-distance goal. The 5.22-mile loop starts and finishes along the sandy shores of Greenbrier Lake with 750 feet of climb and descent on each loop.  The majority of the course is single track, with about half a mile of pavement per loop.  Participants will complete one loop to compete in the…