Gulf of Corinth

The Gulf of Corinth separated the Peloponnese from mainland Greece, with its western entrance opening toward Patras and the Ionian Sea. The fortified approaches near Rio and Antirrio mattered to movement between these waters. The famous battle of Lepanto in 1571 took place farther west in the Gulf of Patras, in the approaches to the Corinthian gulf, rather than at its closed eastern end.

During the Greek War of Independence, fighting also reached the gulf's interior. In September 1827 Frank Abney Hastings brought a small squadron, including the steam-powered Karteria, against Ottoman vessels at the roadstead of Salona, now Itea. His report described the destruction of seven of the nine vessels present. The attack joined a new form of propulsion and heavy naval gunfire to operations along the Greek coast. Corinth's long inlet consequently connected ports and sheltered roadsteads with the wider naval struggle, while its narrow western access shaped the movements of ships.