Kemijoki
 Kemijoki (Swedish: Kemi älv Northern Sami: Giemajohka) with its 550 km (340 mi) length is the longest river in Finland. It runs through Kemijärvi and Rovaniemi before reaching the Gulf of Bothnia at Kemi.At Rovaniemi the Ounasjoki river merges with Kemijoki. The first hydroelectric plant on Kemijoki was constructed in 1949 at Isohaara. A total of 15 power plants have been constructed so far. The plants are owned by Kemijoki Oy and Pohjolan Voima Oy.