The Corinth Canal was formally opened, bisecting the narrow Isthmus of Corinth in Greece to connect the Ionian Sea's Gulf of Corinth with the Aegean Sea's Saronic Gulf.

The Corinth Canal is a canal in Greece that connects the Gulf of Corinth in the Ionian Sea with the Saronic Gulf in the Aegean Sea. Completed in 1893, it cuts through the narrow Isthmus of Corinth and separates the Peloponnese peninsula from the Greek mainland. The canal was dug through the Isthmus at sea level and has no locks. It is 6.4 kilometres in length and at 24.6 metres wide at sea level is impassable for many modern ships. It is currently of little economic importance and is mainly a tourist attraction.

The Isthmus of Corinth is the narrow land bridge which connects the Peloponnese peninsula with the rest of the mainland of Greece, near the city of Corinth. The 6.3 km (3.9 mi) wide Isthmus was known in the ancient world as the landmark separating the Peloponnese from mainland Greece. In the first century AD the geographer Strabo noted a stele on the Isthmus of Corinth, which bore two inscriptions. One towards the East, i.e. towards Megara, reading: "Here is not Peloponnesus, but Ionia" and the one towards the West, i.e. towards the Peloponnese: "Here is Peloponnesus, not Ionia" ; Plutarch ascribed the erection of the stele to the Attic hero Theseus, on his way to Athens.

The Ionian Sea is an elongated bay of the Mediterranean Sea. It is connected to the Adriatic Sea to the north, and is bounded by Southern Italy, including Basilicata, Calabria, Sicily, and the Salento peninsula to the west, southern Albania to the north, and the west coast of Greece, including the Peloponnese.

The Gulf of Corinth or the Corinthian Gulf is an inlet of the Ionian Sea, separating the Peloponnese from western mainland Greece. It is bounded in the east by the Isthmus of Corinth which includes the shipping-designed Corinth Canal and in the west by the Rion Strait which widens into the shorter Gulf of Patras and whose narrowest point has been crossed since 2004 by the Rio–Antirrio bridge. The gulf is bordered by the large administrative divisions : Aetolia-Acarnania and Phocis in the north, Boeotia in the northeast, Attica in the east, Corinthia in the southeast and south and Achaea in the southwest. The tectonic movement across the gulf is comparable to parts of Iceland and Turkey, growing by 10 mm (0.39 in) per year.