This famous event attracts triathletes from around the world, looking to test their endurance with a grueling swim across the Bay, followed by an 18-mile bike ride and 8-mile run over the city’s demanding hills. Not quite ready to take the dive? Get inspired at the Fitness Festival at the finish line at the Marina Green, where vendors and experts will be on hand to lure you into a healthier lifestyle (don’t worry, there’s a beer garden too).