The Marseille tide gauge, zero point for altitudes in France, has been restored. Recognized as a “centenary’s site by the World Meteorological Organization, the site was reopened to the public last September.
This landmark was necessary for the engineer Paul-Adrien Bourdalouë to launch the general leveling of France. The aim was to facilitate the deployment throughout the metropolis of a network, which bears his name, of thousands of landmarks. The tide gauge site made it possible to define the “zero point” of altitudes at the end of the 19th century.