Sweden, officially the Kingdom of Sweden, is a Scandinavian country in Northern Europe. It borders Norway to the west and north and Finland to the east, and is connected to Denmark in the southwest by a bridge-tunnel across the Öresund. At 450,295 square kilometres (173,860 sq mi), Sweden is the third-largest country in the European Union by area. Sweden has a total population of 10.2 million of which 2.4 million has a foreign background. It has a low population density of 22 inhabitants per square kilometre (57/sq mi). The highest concentration is in the southern half of the country. Approximately 85% of the population lives in urban areas, as per a unique Swedish definition where only 200 people constitute an urban system. In contrast, the OECD definition of the smallest urban system is 50.000 people.