The Corinth Canal, an extraordinary feat of engineering, connects the Gulf of Corinth in the Ionian Sea with the Saronic Gulf in the Aegean Sea, cutting a path through Greece’s Isthmus of Corinth. This man-made waterway effectively transforms the Peloponnese peninsula into an island separate from the mainland.
The idea of a canal at this strategic location dates back to the seventh century BC, though it wasn’t realized until the late 19th century, long after the Suez Canal opened in 1869.
Spanning just four miles in length, the Corinth Canal is only 24.6 meters wide at sea level, too narrow for most modern cruise ships but offering a route that bypasses a lengthy 430-mile detour around the Peloponnese.
Constructed as a straight, sea-level channel with an eight-meter depth, the canal requires no locks. Its nearly vertical rock walls rise dramatically, reaching a height of 90 meters above sea level.
The initial canal proposition was suggested by Periander of Corinth in the seventh century BC. Despite its potential, the enormity of the project led to seeking alternative solutions on land. Efforts under Roman Emperor Nero in 67 AD utilized Jewish prisoners from the First Jewish–Roman War, but halted following his death.
Interest in the project persisted through the centuries, intriguing figures like Herodes Atticus in the second century. However, construction did not resume until 1881, following Greece’s independence from the Ottoman Empire. The endeavor faced geological and financial hurdles that led to the bankruptcy of the original construction company, finally reaching completion in 1893.
Despite its strategic promise, the canal’s limited width caused navigation challenges and frequent closures for landslide repairs, lowering anticipated traffic volumes. Expectations hovered around four million net tons of annual traffic, yet by 1906, only half a million net tons were attained.
Currently, the canal holds more touristic than economic value, frequently traversed by smaller recreational vessels. A notable event took place in October 2019 when the cruise ship MS Braemar from Fred. Olsen Cruise Line became the widest and longest vessel to navigate its waters.
Operating on a one-way system, the canal sees ships transit in single-file convoys, with larger vessels requiring tugboat assistance. Approximately 11,000 vessels, predominantly tourist-related, pass through annually.
Bridges—railway, road, and motorway—span the canal at 45 meters above sea level. In 1988, submersible bridges at Isthmia’s eastern and Poseidonia’s western harbors enhanced road crossings.
The canal underwent maintenance in 2021, costing £27 million, reopening in June 2022, and briefly closing again in October for additional restoration, reopening in June 2023.
Additionally, the canal is a venue for notable swimming competitions. Since 2016, it has hosted Greece’s significant “swim across the canal” race, spanning its 6,346-meter length.