Boundaries Between Continents

Boundaries Between Continents

The borders or boundaries separating the various continents of the topography of Earth are a matter of geographical convention. Several slightly different conventions are in use, just as the number of continents is most commonly considered to be seven but may range as low as five, depending on whether the Americas and Eurasia are each considered a single continent. According to the definition of a continent in the strict sense, an island cannot be part of any continent, but in practice most major islands are associated with a continent by convention.

There are three overland boundaries subject to definition:

• between Asia and Africa (dividing Afro-Eurasia into Africa and Eurasia): at the Isthmus of Suez
• between Asia and Europe (dividing Eurasia): along the Bosphorus, the Caucasus and the Urals (historically also north of the Caucasus, along the Kuma–Manych Depression or along the Don River)
• between North America and South America (dividing the Americas): the Isthmus of Panama

While the isthmus between Asia and Africa and that between the two Americas are today navigable, via the Suez and Panama canals, man-made diversions and canals are generally not accepted on their own accord as continent-defining boundaries; the Suez Canal happens to traverse the isthmus between the Mediterranean Sea and Red Sea, dividing Asia and Africa. The remaining boundaries concern the association of islands and archipelagos with specific continents, notably:

• the delineation of Southeast Asia from Australasia
• the delineation between Africa, Europe and Asia in the Mediterranean Sea
• the delineation between Asia and Europe in the Arctic Ocean
• the delineation between Europe and North America in the Atlantic Ocean
• the delineation between North and South America in the Caribbean Sea
• the delineation of Asia from North America in the North Pacific Ocean