It was extended north to Salla and what is now Russia during World War II, though the line is currently moribund beyond Kemijärvi.

On 9 May 1986, a BAE Hawk Mk 51 crashed in Kemijärvi whilst practising for a flight display due to loss of orientation.

Surrounding municipalities are Pelkosenniemi in the north, Salla in the east, Posio in the south and Rovaniemi in the west.

Villages located in the area of the municipality of Kemijärvi are Halosenranta, Hyypiö, Isokylä, Joutsijärvi, Juujärvi, Kallaanvaara, Kostamo, Leväranta, Luusua, Oinas, Perävaara, Ruopsa, Räisälä, Sipovaara, Soppela, Tapionniemi, Tohmo, Ulkuniemi, Varrio and Vuostimo.

The Eastern Lapland area where Kemijärvi is situated is well known for the nearby skiing resorts Suomu, Luosto, Pyhä and Salla, and Ruka in Kuusamo region.