April 10, 2008—A Greek actress uses a special mirror and the sun's rays to light the Olympic torch at Olympia, Greece, during a dress rehearsal of the lighting ceremony for the Athens games on March 24, 2004.

The ceremony evokes the ancient Greek Olympics, which ran every four years from 776 B.C. to A.D. 393. But the Olympic flame, torch, and relay weren't created until the 20th century.

“There was an eternal flame at Olympia, but that had nothing to do with the Olympics,” said David Young, a classical scholar at the University of Florida.

David Romano of the University of Pennsylvania said, “The actual presence of a flame at the modern Olympic Games didn't occur until 1928 at the Olympic Games in Amsterdam.”

Since then, the flame has become an Olympic tradition, and the torches have undergone many innovations to keep the fire bright. (Read full story.)

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