Iceland (Ísland; ) is a Nordic island country in the North Atlantic, with a population of 360,390 The capital and largest city is Reykjavík, with Reykjavík and the surrounding areas in the southwest of the country being home to over two-thirds of the population. Iceland is volcanically and geologically active. The interior consists of a plateau characterised by 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 high latitude almost entirely outside the Arctic Circle. Its high latitude and marine influence keep summers chilly, with most of the archipelago having a tundra climate. According to the ancient manuscript Landnámabók, the settlement of Iceland began in 874 AD when the Norwegian chieftain Ingólfr Arnarson became the first permanent settler on the island. as well as the highest trade union membership in the world. It maintains a Nordic social welfare system that provides universal health care and tertiary education for its citizens. Iceland ranks high in economic, democratic, social stability, and equality, currently ranking first in the world by median wealth per adult. In 2018, it was ranked as the sixth most developed country in the world by the United Nations' Human Development Index, and it ranks first on the Global Peace Index. Since then, the economy has made a significant recovery, in large part due to a surge in tourism. Icelandic culture is founded upon the nation's Scandinavian heritage. Most Icelanders are descendants of Norse and Gaelic settlers. Icelandic, a North Germanic language, is descended from Old West Norse and is closely related to Faroese. The country's cultural heritage includes traditional Icelandic cuisine, Icelandic literature, and medieval sagas. Iceland has the smallest population of any NATO member and is the only one with no standing army, with a lightly armed coast guard.