The first mention of the cape in ancient literature is in the Odyssey (III, 278), which speaks about "holy Sounion, the headland of Athens"
Fugitive slaves, coming from the mines of Laurium, took refuge here in the 8th century BC. The cape was strengthened in 413 BC to protect the export of corn out of Athens during the Peloponnesian War.
Temple of Poseidon
Ruins of the temple of Poseidon, constructed in the 5th century BC over the ruins of a temple constructed in the Archaic Period, are perched above the sea at a height of almost 60 metres. The columns of the temple are 6.10 metres high, with a diameter of 1 metre at the base and 79 centimetres at the top. Their grooves, fewer than usual (16 instead of 20), were intended to resist the weathering action of the sea air. The stone was quarried at nearby Agrileza. The English poet Lord Byron carved his name onto one of the columns.
- Sanctuary of Poseidon and Athena at Sounion - Greek Ministry of Culture