Northern Europe is the geographical region in Europe roughly north of the southern coast of the Baltic Sea, which is about 54°N. Narrower definitions may be based on other geographical factors such as climate and ecology. A broader definition would include the area north of the Alps. Countries which are central-western (such as Belgium and Switzerland), central (such as Austria) or central-eastern (such as Hungary and Poland) are not usually considered part of either Northern or Southern Europe.
Northern Europe might be defined roughly to include some or all of the following areas: British Isles, Fennoscandia, the peninsula of Jutland, the Baltic plain that lies to the east and the many islands that lie offshore from mainland Northern Europe and the main European continent. In some cases, Greenland is also included.
The area is partly mountainous, including the northern volcanic islands of Iceland and Jan Mayen, and the mountainous western seaboard, Scotland and Scandinavia, and also often includes part of the large plain east of the Baltic sea.
The entire region’s climate is at least mildly affected by the Gulf Stream. From the west, climates vary from maritime and maritime subarctic climates. In the north and central regions, the climate is generally subarctic or Arctic and to the east, climates are mostly subarctic and temperate/continental.
Just as both climate and relief are variable across the region, so too is vegetation, with sparse tundra in the north and high mountains, boreal forest on the north-eastern and central regions; temperate coniferous forests and temperate broadleaf forests growing in the south, west and temperate east. Various definitions of Northern Europe often include the Nordic countries, and may also include some or all of the Baltic states, the British Isles, northern Germany, northern Belarus and northwest Russia. Countries in Northern Europe generally have developed economies and some of the highest standards of living in the world. They often score highly on surveys measuring quality of life, such as the Human Development Index. Aside from the United Kingdom, they generally have a small population relative to their size, most of whom live in cities. Most people living in Northern Europe are traditionally Protestant Christians, although many are non-practicing.