The Chemin de fer des Côtes-du-Nord, the Côtes-d'Armor today, was a 1,000 mm, metre gauge, railway in Côtes-du-Nord, France, although there were a few kilometres of line in Finistère and Ille-et-Vilaine. The first lines opened in 1905 and final closure was in 1956. The lines were a voie ferrée d'intérêt local system with a total extent of 457 kilometres (284 mi).

The Réseau Breton (RB) is a 1,435 mm, standard gauge, and former 1,000 mm, metre gauge, railway in Finistère, France, with a few kilometres of line in Côtes d'Armor, Ille-et-Vilaine and Morbihan. The hub of the system was Carhaix. The metre gauge lines were built with the capacity to be easily converted to standard gauge if necessary.