Poseidon Sanctuary Ruins

On the island of Poros, in the Saronic Gulf, the ruins of the Sanctuary of Poseidon occupy a hilltop site known as Kalaureia (or Kalavria), roughly 200 metres above sea level and a short distance north of Poros Town. This is not the same site as the far larger and better-known Temple of Poseidon at Cape Sounion near Athens, on the Attic mainland — the Poros sanctuary is a separate, older site with its own distinct history.

Archaeological evidence shows the hill was in use from at least the Early Bronze Age, but the main Doric temple visible in the ruins today was built around 520 BC. It measured roughly 27 by 14 metres, with six columns across its short sides and twelve along its long sides. From the 7th century BC, the sanctuary served as the seat of the Kalaureian League, a religious and political alliance of city-states including Athens, Aegina and Epidaurus, formed to protect their shared trade and independence.

The site's most famous historical episode came in 322 BC, when the Athenian orator Demosthenes, fleeing capture by the Macedonian regent Antipater, took refuge at the sanctuary and is said to have poisoned himself there rather than be taken prisoner.

Swedish archaeologists began excavating the site in 1894 — the first Swedish archaeological expedition in Greece — and fieldwork has continued intermittently since 1997. Little remains standing above foundation level; among the few surviving fragments is a large marble foot, all that is left of a statue of Poseidon estimated to have stood around five metres tall, now kept in the Archaeological Museum of Poros. The hilltop rewards the climb with sweeping views over the Saronic Gulf, and many visitors combine a day of sightseeing with a private gulet charter along the Greece coast.