Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Oceanto the north, the Atlantic Ocean to the west, and the Mediterranean Sea to the south. To the east and southeast, Europe is generally considered as separated from Asia by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and BlackSeas, and the waterways of the Turkish Straits.Yet the borders of Europe—a concept dating back to classical antiquity—are arbitrary, as the primarily physiographic term “continent” also incorporates cultural and political elements. Europe is the world’s second-smallest continent by surface area.