"The Greatest." "The Louisville Lip." "The Champ." Whatever you call him, you can't deny that Muhammad Ali is a living legend and one of the greatest athletes of the modern era. He launched into boxing history with the name Cassius Clay at the 1960 Summer Games in Rome, where he won a gold medal in the light-heavyweight division. Later, as a professional boxer, Ali won the world heavyweight title three times by floating like a butterfly and stinging like a bee. At the Muhammad Ali Center, in the champ's hometown, you can see video of his greatest fights and pound the heavy bag in a re-creation of Ali's training facility.