Ancient Corinth sat on the Isthmus of Corinth—the narrow land bridge (6.4 km wide) connecting the Peloponnese peninsula to mainland Greece. Strategically positioned between the Gulf of Corinth (Ionian Sea) and the Saronic Gulf (Aegean), it controlled both land and maritime trade routes.
Key ruins: Temple of Apollo (540 BCE), Acrocorinth (fortified acropolis), Roman forum, Peirene Fountain, and the Diolkos—an ancient paved trackway for dragging ships across the isthmus.