Iceland ⁱ/ˈaɪslənd/ (Icelandic: Ísland, IPA: [ˈislant]; see Names for Iceland), officially called Republic of Iceland and sometimes its counterpart Lýðveldið Ísland in Icelandic (for example this is a part of the name of the Constitution of Iceland, Stjórnarskrá lýðveldisins Íslands), is a Nordic European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. The country has a population of about 320,000 and a total area of 103,000 km² (40,000 sq mi). The capital and largest city is Reykjavík, with the surrounding areas in the southwestern region of the country being home to two-thirds of the country's population. Iceland is volcanically and geologically active. The interior mainly consists of a plateau characterised by sand fields, mountains and glaciers, while many glacial rivers flow to the sea through the lowlands. Iceland is warmed by the Gulf Stream and has a temperate climate despite a high latitude just outside the Arctic Circle.