The 121st annual Boston Marathon, the oldest annually contested race of its kind in the world, once again takes to the streets of Boston and points west on April 17. This grand tradition boasts a field of elite runners and wheelchair competitors, including 44 top athletes from 10 countries who join an overall crowd of 30,000 vying for glory as they close in on the Copley Square finish line. Staggered start times—the mobility impaired division begins at 8:50 a.m. and the final wave gets underway at 11:15 a.m. in Hopkinton—insure race action all along the 26.2-mile course for eager spectators, who gather from all around the world to cheer on both the world-class performers and the hundreds of recreational runners striving for their personal bests.