Sphaeria

Sphaeria or Sphairia , later called Hiera , is a former island of ancient Argolis described by Pausanias as in the immediate vicinity of Calaureia, and separated from the mainland by a strait so narrow and shallow that there was a passage over it on foot.
Pausanias wrote that on the island was the tomb of Sphaerus , who was a charioteer of Pelops. In addition, he wrote that according to legend Aethra saw Athena in a dream, and Athena told her to go to the island to give offerings to Sphaerus. Aethra went to the island and Poseidon had intercourse with her there. For this reason Aethra set up a temple of Athena Apaturia on the island. Due to this the name of the island changed to Sacred Island. Furthermore, she also established a custom for the Troezenian maidens of dedicating their girdles before wedlock to Athena Apaturia.

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