The largest of the world's continents. With its peninsular extension, commonly called the continent of Europe, it is the major portion of the broad east-west extent of the Northern Hemisphere landmasses. In many ways Asia is more a cultural concept than a physical entity. There is no logical physical separation between Asia and Europe, and even Africa is separated from Asia merely by the width of the Suez Canal. For convenience, however, the Eurasian landmass is considered to be divided by the Ural Mountains into Europe in the west and Asia in the east. Thus restricted Asia has an area of about 17,700,000 mi2 (45,800,000 km2), about one-third of the land area of the Earth. In the north, mainland Siberia reaches past the 77th parallel. Southward, India and Sri Lanka (Ceylon) reach nearer than 10° north of the Equator, while the Indonesian islands extend more than 10° south of the Equator. The continental heart of Asia is more than 2000 mi (3200 km) from the nearest ocean. These vast distances have great significance in the climates and vegetation of Asia and thus in the erosional and depositional patterns of the land (Fig. 1).  See also: Continent; Europe