Isthmía - Temple of Poseidon

The plan of the temple of Poseidon, built in 460 B.C. as successor to an earlier temple of the seventh century B.C., can be traced on the ground: it was a Doric peripteral temple with the classical proportions of 6 x 13 columns. It was damaged by fire in 394 B.C. and thereafter rebuilt. Northeast of the temple was the theater, to the southeast the stadion, which was rather later (fourth century B.C.).

The ancient buildings were destroyed in the A.D. sixth century, during the reign of Justinian, when the stones were used in the construction of a Byzantine fortress (remains east of theater), part of the defenses built across the Isthmus of Corinth, and constantly renewed in later centuries, to protect the Peloponnese from attackers coming from the north. The defensive wall ran roughly parallel to the present canal and was six Roman miles long (1 Roman mi = 1,000 paces = 1,618yd) - as the name of the village of Examília still indicates.

Remains dating from the Mycenaean period (13th century B.C.) have been found south and southeast of the temple of Poseidon. There are also substantial remains of a defensive wall built in 480-479 B.C. and restored in 197 B.C. and again in A.D. 253. This was followed by the work carried out in the reign of Justinian (A.D. 540); and there are references to further repair and strengthening of the wall in late Byzantine times and during the Venetian period.