Europe is by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, and by the Caucasus Mountains to the southeast. Europe is washed upon to the north by the Arctic Ocean and other bodies of water, to the west by the Atlantic Ocean, to the south by the Mediterranean Sea, and to the southeast by the Black Sea and the waterways connecting it to the Mediterranean.
Yet the borders for Europe—a concept dating back to classical antiquity—are somewhat arbitrary, as the term continent can refer to a cultural and political distinction or a physiographic one.
Europe is the world's second-smallest continent by surface area, covering about 10,180,000 square kilometres (3,930,000 sq mi) or 2% of the Earth's surface and about 6.8% of its land area.
Of Europe's approximately 50 states, Russia is the largest by both area and population, while the Vatican City is the smallest. Europe is the third most populous continent after Asia and Africa, with a population of 731 million or about 11% of the world's population; however, according to the United Nations (medium estimate), Europe's share may fall to about 7% in 2050.
Europe, in particular Ancient Greece, is often considered to be the birthplace of Western culture. It played a predominant role in global affairs from the 16th century onwards, especially after the beginning of colonialism. Between the 17th and 20th centuries, European nations controlled at various times the Americas, most of Africa, Oceania, and large portions of Asia. Both World Wars were ignited in Central Europe, greatly contributing to a decline in European dominance in world affairs by the mid-20th century as the United States and Soviet Union took prominence. During the Cold War Europe was divided along the Iron Curtain between NATO in the West and the Warsaw Pact in the East. European integration led to the formation of the Council of Europe and the European Union in Western Europe, both of which have been expanding eastward since the fall of the Soviet Union in 1991.
London is the capital of the United Kingdom and England. It has been an influential city for two millennia and its history goes back to its founding by the Romans. The city's core, the ancient City of London, still retains its limited medieval boundaries. However, since at least the nineteenth century, the name "London" has also referred to the whole metropolis that has developed around it. Today the bulk of this conurbation forms the London region and the Greater London administrative area, with its own elected mayor and assembly.
Paris is the capital of France and the country's largest city. It is situated on the river Seine, in northern France, at the heart of the Île-de-France region. The city of Paris, within its limits largely unchanged since 1860, has an estimated population of 2.300.000, but the Paris aire urbaine (or metropolitan area) has a population of over 11 million, and is the most populated metropolitan area in the Eurozone.
Berlin is the capital city and one of sixteen states of Germany. With a population of 3.4 million within its city limits, Berlin is Germany's largest city. It is the second most populous city and the eighth most populous urban area in the European Union. Located in northeastern Germany, it is the center of the Berlin-Brandenburg metropolitan area, comprising 5 million people from over 190 nations.
Madrid is the capital and largest city of Spain. It is the third-most populous municipality in the European Union after Greater London and Berlin, and its metropolitan area is the fourth-most populous urban area in the European Union after Paris, London, and the Ruhr Area.
