The Temple of Poseidon in Sounion, Greece.
Built around 444-440 BC and perched 60 meters (200 feet) above the sea, the Temple of Poseidon at Cape Sounion in Greece is considered by many to be one of the major monuments during the Golden Age of Athens.
Though the first version of this temple was likely destroyed by the Persians in 480 BC during an invasion led by Xerxes, this new version stands as a stronger, more fortified structure; commissioned by the Athenian statesman, Pericles. Made out of marble instead of its predecessor's tufa, all that remains now of this once wondrous temple are 16 of its original 38 columns.
Most probably, the temple stood as not only a monument of worship to Poseidon, but a request for safe passage, as the surrounding area was primarily used as a major port for those entering and exiting Greece.