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The Corinth Canal (Greek: Dhioryga tis Korinthou) is a canal that connects the Gulf of Corinth with the Saronic Gulf in the Aegean Sea. It cuts through the narrow Isthmus of Corinth and separates the Peloponnese from the Greek mainland, arguably making the peninsula an island.
Construction started in 1881. It was completed in 1893. The canal was proposed in classical times and an abortive effort was made to build it in the 1st century CE.