Aquitaine (UK: /ˌækwɪˈteɪn/, US: /ˈækwɪteɪn/; French: [akitɛn] ; Occitan: Aquitània [akiˈtanjɔ]; Basque: Akitania; Poitevin-Saintongeais: Aguiéne), archaic Guyenne or Guienne (Occitan: Guiana), is a historical region of southwestern France and a former administrative region. Since 1 January 2016 it has been part of the administrative region of Nouvelle-Aquitaine. It is situated in the southwest corner of metropolitan France, along the Atlantic Ocean and the Pyrenees mountain range on the border with Spain. It is composed of five departments: Dordogne, Lot-et-Garonne, Pyrénées-Atlantiques, Landes, and Gironde. The Romans established Gallia Aquitania as a province. In the Middle Ages, Aquitaine was a kingdom and a duchy whose boundaries fluctuated considerably. For most of Aquitaine's written history, Bordeaux has been a vital port and administrative centre.