The Kingdom of Sweden is a Nordic country in Scandinavia. It is bordered by Norway in the west, Finland in the northeast, the Skagerrak Strait and the Kattegat Strait in the southwest, and the Baltic Sea and the Gulf of Bothnia in the east. It is connected to Denmark in the southwest by the Oresund Bridge. Sweden has a low population density except in its metropolitan areas, with most of the inland consisting of forests. The country has large natural resources of water, timber, and iron ore. Its citizens enjoy a high standard of living in a country that is generally perceived as modern and liberal. Following the end of the Viking Age, Sweden became part of the Kalmar Union together with Denmark and Norway (Finland at this time was a part of the Swedish kingdom). Sweden left the union in the beginning of the 16th century, and more or less constantly battled its neighbours for many years, especially Russia and the still united Denmark-Norway, which never completely accepted Sweden leaving the union. In the 17th century Sweden extended its territory through warfare and became a Great Power, twice its current size. By 1814 Sweden had lost its empire as well as Finland, previously an integral part of the Kingdom of Sweden. Since 1814, Sweden has been at peace, adopting a non-aligned foreign policy in peacetime and neutrality in wartime.