Telesterion

A great hall in Eleusis, Telesterion ("Initiation Hall" from Gr. τελείω, to complete, to fulfill, to consecrate, to initiate) was one of the primary centers of the Eleusinian Mysteries. Devoted to Demeter and Persephone, these initiation ceremonies were the most sacred and ancient of all the religious rites celebrated in Greece. At some point in the 5th century BCE, Iktinos, the great architect of the Parthenon, built the Telesterion big enough to hold thousands of people. In about 318 BCE, Philon added a portico with twelve Doric columns. The site of the Telesterion is believed to have had some temple since the 7th century BCE, or the time of the Homeric Hymn to Demeter one of 33 Homeric Hymns (650-550 BCE); the Telesterion had ten different building phases.

The Athenians used several calendars, each for different purposes. The festival of Eleusinia was celebrated each year in Eleusis and Athens for nine days from the 15th to the 23rd of the month of Boedromion (in September or October of the Gregorian calendar); because the festival calendar had 12 lunar months, the celebrations were not strictly calibrated to a year of 365 days. During the festival, Athens was crowded with visitors.

As the climax of the ceremonies at Eleusis, the initiates entered the Telesterion where they were shown the sacred relics of Demeter and the priestesses revealed their visions of the holy night (probably a fire that represented the possibility of life after death). This was the most secretive part of the Mysteries and those who had been initiated were forbidden to ever speak of the events that took place in the Telesterion.

It was destroyed by the Persians after the Battle of Thermopylae, when the Athenians withdrew to Salamis in 480 BCE and all of Boeotia and Attica fell to the Persian army, who captured and burnt Athens. After the defeat of the Persians, the Telesterion was rebuilt some time later by Pericles.

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