The Antikythera Mechanism, a mechanical brass calculator used to predict eclipses of the sun and moon was also probably used to set dates for the Olympic games. The device was taken from a shipwreck in 1901, near an island of its namesake.
Researchers, who've studied the intricate gears, dials and inscriptions used 3-D & X-Ray technology to decipher the clues, leading the researchers to believe that the device played a significant role in calculating dates for the games' 4 year cycle.
The complex device dates to 200 BC and was originally thought to have originated in the eastern Mediterranean. However, the names inscribed on the device pointed the origin of the device to Corinth.