Côtes-d'Armor is a département in the northwest of France.
Côtes-du-Nord was one of the original 83 départements 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 région of Bretagne and is surrounded by the départements of Finistère, Morbihan, and Ille-et-Vilaine, with the English Channel on the north.
The inhabitants of the département are called Costarmoricains.
The Breton language has become an intense issue in many parts of Brittany, and many Breton-speakers advocate for bilingual schools. Gallo is also spoken in the east and is offered as a language in the schools and on the baccalaureat exams.