Côtes-d'Armor (Breton:Aodoù-an-Arvor) is a department in the north of Brittany, in northwestern France.
Côtes-du-Nord was one of the original 83 departments created during the French Revolution on March 4, 1790. It was created from part of the former province of Brittany. Its name was changed in 1990 to Côtes-d'Armor (ar mor meaning the sea in Breton). The name also has a historical connotation recalling the Roman province of Armorica.
Côte-d'Armor is part of the current administrative region of Bretagne and is surrounded by the departments of Finistère, Morbihan, and Ille-et-Vilaine, with the English Channel on the north.
The department was initially named Côtes-du-Nord ("Northern-Coasts"), referring to its geographical situation in Brittany. In the 90's, it was said that "Northern" could limit tourism, and the name of the department was changed to the French-Breton hybrid nmae Côtes-d'Armor. In Breton, Armor means the sea, and was used to named all parts of Britanny close to the coasts, as opposed to Argoat, the land, which was used to name the inner parts of Britanny.