Pyramide de Cassini

About

The Cassini Pyramid (or Cassini Pyramid) was built in Villejuif in 1742 by Jacques Cassini, together with the pyramid of Juvisy, to measure the terrestrial meridian and serve as a starting point for his map of France. It was listed as historical monuments by order of 29 October 1928. It was erected by Cassini, his son Caesar, and astronomer Nicolas-Louis de Lacaille, on the orders of King Louis XV, and is located exactly on the meridian of Paris measured in 1683.

It is located in a private passage at 157 bis of Avenue de Paris, at a point reaching 105 meters of altitude. The pyramid is eroded and slightly inclined, which gives it the appearance of Tower of Pisa.