A prytaneion (Ancient Greek: Πρυτανεῖον, Latin: prytanēum) was seat of the prytaneis (executive), and so the seat of government in ancient Greece. The term is used to describe any of a range of ancient structures where officials met (normally relating to the government of a city), but the term is also used to refer to the building where the officials and winners of the Olympic Games met at Olympia. The prytaneion normally stood in the centre of the city, in the agora.
In general in ancient Greece, each state, city or village possessed its own central hearth and sacred fire, the prytaneion, representing the unity and vitality of the community. The fire was kept alight continuously, tended by the king or members of his family. The building in which this fire was kept was the prytaneion, and the chieftain (the king or prytanis) probably made it his residence. The building contained the holy fire of Hestia, the goddess of the hearth, and symbol of the life of the city.
The term prytanis (pl. prytaneis) is generally applied specially to those who, after the abolition of absolute monarchy, held the chief office in the state. Rulers of this name are found at Rhodos as late as the 1st century BC.