A new analysis of the Antikythera Mechanism, which is thought to be the first analogue computer, has shown that apart from predicting solar movements it was also used to plan for the Olympics.
The device, which was found in a first-century shipwreck, is made up of brass dials and cogs.
A previous analysis concluded that the device was used to predict solar and lunar cycles, but new scanning technology has revealed that it was also used to date the Olympic Games.
Tony Freeth, a member of the Antikythera Mechanism Research Project, told the BBC that he was "astonished" at the discovery.
"The Olympiad cycle was a very simple, four-year cycle and you do not need a sophisticated instrument like this to calculate it. It took us by huge surprise when we saw this," he said.
"But the Games were of such cultural and social importance that it is not unnatural to have it in the Mechanism."
By using 3D scanning the team found the words 'Isthmia', 'Olympia', 'Nemea' and 'Pythia' (part of the precursor games to the main Pan-Hellenic competition) etched on one of the cogs.
The Antikythera Mechanism has fascinated scholars since it was identified. It was so far advanced that similar mechanisms were not created until over 1,000 years later.
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