Iceland is a Nordic island country between the North Atlantic and Arctic Oceans, on the Mid-Atlantic Ridge between North America and Europe. It is culturally and politically linked with Europe and is the region's westernmost and most sparsely populated country. Its capital and largest city is Reykjavík, which is home to about 36% of the country's roughly 380,000 residents. The official language of the country is Icelandic. Iceland is on a rift between tectonic plates, and its geologic activity includes geysers and frequent volcanic eruptions. The interior consists of a volcanic plateau with sand and lava fields, mountains and glaciers, and many glacial rivers flow to the sea through the lowlands. Iceland is warmed by the Gulf Stream and has a temperate climate, despite a latitude just south of the Arctic Circle. Its latitude and marine influence keep summers chilly, and most of its islands have a polar climate.