Carhaix-Plouguer (; ), commonly known as just Carhaix (), is a commune in the French department of Finistère, region of Brittany, France. The commune was created in 1957 by the merger of the former communes Carhaix and Plouguer. Geography Carhaix is located in the Poher, an important territory of Brittany, sandwiched between the Arrée Mountains to the north and the Black Mountains to the south. The agglomeration developed mainly on a plateau located at 140 meters above sea level, gently sloping towards the west, the highest elevations being eastwards beyond the agglomeration towards 155–169 meters above sea level. This plateau is limited to the north by the valley of the Hyères (60 meters elevation that imposed the construction of an aqueduct in Roman times to cross it), which flows to 80 meters above sea level, and south by the stream of the Madeleine whose route was taken again by the channel of Nantes in Brest. The Hyères sometimes causes serious floods: in March 1903, the Sainte-Catherine chapel located in Plounevézel but at the limit of Carhaix, had water up to the roof and in 1910 to the stained glass windows. Geologically, Carhaix is located in the center of the Châteaulin basin, which consists mainly of slate and sandstone schists and forms a topographic depression between the Arrée Mountains and the Black Mountains. Having become communes at the French Revolution, Carhaix and Plouguer merged in 1957 and took the name of Carhaix-Plouguer. As early as 1862, the municipal council of Carhaix had expressed a wish in this direction. Carhaix station has rail connections to Guingamp. Climate Carhaix-Plouguer has a oceanic climate (Köppen climate classification Cfb). The average annual temperature in Carhaix-Plouguer is . The average annual rainfall is with December as the wettest month. The temperatures are highest on average in August, at around , and lowest in January, at around . The highest temperature ever recorded in Carhaix-Plouguer was on 9 August 2003; the coldest temperature ever recorded was on 14 January 1985. Name The name in Breton of the commune is Karaez-Plougêr. In a charter signed by the Count of Cornouaille, Hoel, to "donate a villa near Caer Ahes, in which is the church of sanctus Kigavus (saint Quijeau), we find the oldest form of name of Carhaix, close and contemporary to those mentioned in medieval novels. The charter is necessarily prior to the death of Hoel (1084). Saint-Quijeau