According to the ancient traveler and geographer, Pafsania...

… From antiquity, Poros consists of two isles-Sferia and Kalavria (meaning pleasant breeze), which was initially dedicated to Apollo who then transferred it over to Poseidon in exchange for Delphi.

Kalavria is a larger, very wooded area than Sferia with an abundant water supply. On the other hand, Sferia is basically a cliff formed by some volcanic eruption.

The name “Kalavria” in ancient texts is found in different variations such as “Kalavrea”, “Kalavree” and “Kalavreia”. It must have gotten its name from a combination of two words- KALH (good) and AVRA (breeze) which the island has plenty of and originated from the sea across as well as the dense pine forests along with the olive groves of the island.

Another opinion on how the name came up is that Kalavria was named after Kalavro, the son of Poseidon and patron of the island. Prior to the given name, Kalavria, it was also called Irini, Anthi, Yperi, Anthidonia and Skelerdia.

Sferia was named after Pelopa’s charioteer, Sfero who had left on his own or was possibly persecuted by Pelopa’s servants and was chased all the way to Trizina.

Pelopa’s sons, Pithefs and Trizin, reigned there after their father pursued them from Pissa (the city-state near ancient Olympia). Sfero asked for and was granted asylum by them. He was buried in Sferia when he died.

According to Pafsania, goddess Athena, either because Sferos was favored by her or because she wanted to thank Poseidon in some way, appeared in Aethra’s dream. Aethra was the daughter of Pitthea, the king of Trizina, and Athena told her (in her dream) to go to Sferia and make a sacrifice on Sfero’s tomb. Aethra went to Sferia where she met Poseidon who seduced and slept with her. As for Athena’s deception, not only was Aethra not upset, but she built the temple of Apatouria there for her.

From then on, virgins from Trizina visit the temple and dedicate their chastity belts to Athena of Apatouria before they get married. Amazingly, this way, the young women of Trizina were capable of covering any “foolish mistakes” made prior to their wedding. That is the reason why Sferia was called Hiera (Holy).

This legendary shrine was probably situated at Saint George’s temple or a little more to the east where an old reservoir is located today. A few remains of this ancient sanctuary can be found in some of Poros’ old houses around St. George’s church