Many think the traditional five-week Triple Crown rotation of Kentucky Derby, Preakness and Belmont needs a shake up as modern horse trainers do not like to race horses three times in five weeks.

Thirteen horses have won the Triple Crown in American Thoroughbred racing history. Here's a look at the winners and the history of the Triple Crown:

The attempt to win the Kentucky Derby, the Preakness and the Belmont felt way more impossible just a decade ago.