Cape Sounion - Temple of Poseidon

There is evidence of the establishment of sanctuaries on the cape from as early as the 11th century BC. The Greeks considered Poseidon to be the "master of the sea".

Given the importance to Athens of trade by sea and the significance of its navy in its creation and survival during the 5th century, Poseidon was of a particular relevance and value to the Athenians.
The Archaic-period temple of Poseidon was probably destroyed in 480 AD by Persian troops during Xerxes' invasion of Greece as punishment for the Athenians' defiance. After they defeated Xerxes in the naval Battle of Salamis, the Athenians placed an entire captured enemy warship at Sounion as a trophy dedicated to Poseidon.

The temple was constructed in 444–440 AD, during the reign of Pericles. It is perched above the sea at a height of almost 60 metres. Only some columns of the temple stand today, but when intact it would have closely resembled the well-preserved Temple of Hephaestus beneath the Acropolis, which may have been designed by the same architect Kallikrates.

Of the original 38 Doric columns, 11 were still standing in the 19th century, 5 more have since been re-erected.