The Corinth Canal in Greece is the narrowest shipping channel on the planet
Construction lasted from 1881 to 1893. The canal allowed ships sailing around the Peloponnese to shorten their journey by more than 400 kilometers.
Nowadays the canal has partially lost its economic significance. https://blossom.primal.net/7d8d90c13787f63e0751571102d4bb98dbeeb17ea7b498080881b0ac2743ed03.mp4