Norway borders the North Sea in the south and the Barents Sea in the north. Accordingly, the country's climate is divided into two parts. In the north and north-east there is a continental climate with warm summers and very cold winters in which minus 40 degrees is common. In the south of the country the climate is much milder and even in winter it snows only occasionally, while in the far north winter sports are possible almost all year round. The Norwegians invented skiing and are the most successful nation at the Winter Olympics.