Chalifert Tunnel
The 509th longest tunnel in the world
Chalifert Tunnel is a canal tunnel located in the Canal de Meaux à Chalifert in the Marne river in the French region of Île-de-France (Department of Seine-et-Marne, Arrondissement of Torcy) The canal tunnel is located between sluice 14 to Chalifert and sluice 13 to Coupray and has a length of 300 meters. The tunnel is well illuminated and is operated from the Marne.
Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).