Tornio is a city and municipality in Lapland, Finland. The city forms a cross-border twin city together with Haparanda on the Swedish side. The municipality covers an area of 1,348.83 square kilometres (520.79 sq mi), of which 161.59 km2 (62.39 sq mi) is water. The population density is 18.4 inhabitants per square kilometre (48/sq mi), with a total population of 21,837. It borders the Swedish municipality of Haparanda. In spite of being a border city Tornio is unilingually Finnish with a negligible number of native Swedish speakers, although this does not count Finnish bilinguals.