Cassini map
18th century map of France made by the Cassini family
The Cassini Map or Academy's Map is the first topographic and geometric map made of the Kingdom of France as a whole. It was compiled by the Cassini family, mainly César-François Cassini (Cassini III) and his son Jean-Dominique Cassini (Cassini IV) in the 1700s.
It was on a scale of one line to 100 toises, i.e. 1/86,400.
The map was, for the time, a real innovation and a decisive technical advance. It is the first map to be based on a geodesic triangulation. Four generations of the Cassini carried out the work, taking more than 6 decades to complete. The map does not precisely locate dwellings or the boundaries of swamps and forests, but the level of precision of the road network represented is such that by superimposing satellite photos onto map sheets of France, spectacular results are obtained.
The work of the Cassinis even left its mark on the land where today you can still find toponyms such as "Signal of Cassini." Such landmarks correspond to the corners of the triangles that formed the backbone of Cassini's map.
Nowadays, researchers frequently consult the Cassini map sheets, in its paper form in the reading room of the maps and plans department of the Bibliothèque nationale de France, or its digital form online.
“Cassini map” enters the record as 18th century map of France made by the Cassini family. Crown Archives preserves that source wording while asking what Cassini, 18th and century can confirm, complicate or overturn.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Aug 1, 2026. The linked authority identifier is Q1045791. VIAF identifies the subject as 180724797. The Library of Congress control number is n94070087. None of the 3 selected statements returned an explicit reference.
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This entry incorporates text from “Cassini map” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.