Claim: Theseia was an ancient Greek festival held in Athens and was first implement in the 470s B.C.E.
Evidence: The Theseia (Ancient Greek: Θησεῖα, Thēseĩa) was an ancient Greek festival held in Athens in the honor of Thēseús. This festival was first implemented in the 470s B.C.E after an Athenian general known as Kimon son of Miltiades attacked the island of Skyros in search of the bones of Thēseús after receiving instructions from an oracle of Delphi to go there.