Ancient Greek city-states agreed to pause their wars for the Olympics

Every four years, heralds travelled between rival Greek city-states announcing the ekecheiria, a sacred truce that was supposed to protect athletes, spectators and officials traveling to and from Olympia. The truce let bitter enemies compete and watch side by side, though historians note it was broken more than once when it suited a city's interests.

— Nigel Spivey, The Ancient Olympics — 2004
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