region of ancient Greece occupying most of the Isthmus of Corinth (which connects the Peloponnese with the rest of Greece) and some of the northeastern part of the Peloponnese
isthmus of corinth
geographical name(Cor-inth)
inlet of the Ionian Sea in central Greece west of the Isthmus of Corinth, a neck of land 20 miles (32 kilometers) long connecting the Peloponnese with the rest of Greece