10. Indianapolis 500
One of the triple crown of motor sports, the Indianapolis 500 has run since 1911, and features racers moving around a 2.5 mile oval for some 200 laps (or 500 miles). The event is billed out as the single largest yearly sporting event in the world, with close to 300,000 attendees at the speedway, and millions of viewers worldwide. Over 50 drivers, spectators, and crew members have died in preparation for or during the Indianapolis 500.