Isthmia

Isthmia is an ancient sanctuary of Poseidon and important archaeological site and museum located on the Isthmus of Corinth in Greece. Situated on the territory of the ancient city-state of Corinth, it was famous in antiquity for the Isthmian Games and its Temple of Poseidon.
Isthmia is located on the key land route connecting Athens and central Greece with Corinth and the Peloponnese. Its location on the Isthmus, between the major Corinthian ports of Lechaeum on the Gulf of Corinth and Cenchreae on the Saronic Gulf, made Isthmia a natural site for the worship of Poseidon, god of the sea and also of mariners. Isthmia sits on a very active fault line, and Poseidon's role as "Earth-holder" in causing and averting earthquakes is another reason Isthmia became the center of athletic and religious festivals in his honor. The Games at Isthmia were second in significance only to those at Olympia.

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