Marseille marigraph

The Marseille marigraph stands as a cylindrical tower equipped with mechanical and modern radar systems that continuously measure Mediterranean Sea level variations with exceptional precision.

Constructed in 1883 and officially establishing France's zero altitude reference point on January 1, 1897, this scientific instrument has maintained nearly uninterrupted sea level measurements for over 140 years.

This classified historical monument represents Marseille's deep maritime heritage and serves as the fundamental reference point for altitude measurements across France and its overseas territories.

Located on the Corniche near Villa Valmer, the facility houses both original mechanical equipment and modern digital sensors that provide essential data for climate change research and coastal management.

The marégraphe contains one of the world's rare integrating mechanisms with a bronze rivet covered in platinum-iridium alloy that serves as the absolute reference point for French territorial altitudes.

Location: 7th arrondissement of Marseille

Inception: 1883

GPS coordinates: 43.27860,5.35361

Latest update: July 25, 2025 23:09