9. Boilermaker 15K Road Race

The Buzz -- Named not only the largest 15K race in the nation but one of the most competitive, this annual event draws more than 10,000 participants, including Olympic athletes and top runners from across the globe. The race – begun by Earle C. Reed in 1976 as a civic gift – is now sponsored by major financial, retail, and communications companies and is a favorite of local and international runners. It is also affiliated with the Hall of Fame, which honors athletes who make exceptional advances and contributions to the sport of distance running.