The sanctuary of Poseidon lies on a very favorable location at the isthmus of Korinth. Already in the 6th Century festivals were held every other year and participants came from all parts of the Greek world. The sanctuary of Poseidon was host to many important assemblies in Greek history including:
Aside from these Pan Hellenic events, the most the most important single text of diplomatic importance was a treaty between Athens and Sparta commemorating the conclusion of peace sometime during the 4th Century. Otherwise, there are very few epigraphical indications of other treaties, honors or diplomatic events.