Continental Divide

Continental Divide

A continental divide is an area of raised terrain that separates a continent’s river systems that feed to different basins.


6 - 12+


Earth Science, Geography, Human Geography, Physical Geography

NGS Resource Carousel Loading Logo
Loading ...

A continental divide is a naturally occurring boundary or ridge separating a continent’s river systems. Each river system feeds into a distinct ocean basin, bay, or sea.

Continental divides are broad, continent-wide example of drainage divides, sometimes just called divides. Divides are boundaries that separate drainage basins or watersheds of all sizes. Drainage divides, regardless of scale, occur in raised terrain such as mountain ranges or hills.

Generally, precipitation that falls on one side of the divide will flow to one basin and precipitation that falls on the other side will flow to another basin.

In some cases, water runs toward an endorheic basin, such as a saline lake or salt flat. Endorheic basins, which do not connect to an ocean or other large body of water, usually occur in desert areas. Much of the Sahara Desert in Africa, for example, is an endorheic basin. This means that rivers and streams that flow into Lake Chad, on the edge of the Sahara, have no outlet to either the Mediterranean Sea or the Atlantic or Indian Oceans.

Continental divides are found on every continent. Continents that are bordered by more than two bodies of water may have more than one continental divide. For example, North America has between three and five divides. Scientists have not yet agreed on a specific number because the exact border between ocean basins is not universally accepted.

Some continental divides span multiple continents. For example, the Continental Divide of the Americas, or the Great Divide, runs through much of North and South America. It separates the water that runs toward the Pacific Ocean from the water that runs toward the Atlantic and Arctic Oceans and the Gulf of Mexico. This divide runs from Cape Prince of Wales in western Alaska, through the Rocky Mountains of western Canada and the continental United States, then through the Sierra Madre Occidental mountains in Mexico, through Central America and along the Andes Mountains of South America.

Fast Fact

Great Dividing Range
The Great Dividing Range is a series of mountain ranges and escarpments that runs the entire length of eastern Australia. Despite its name, the Great Dividing Range is only sometimes considered a continental divide. It separates water flowing to the Pacific Ocean from water flowing to the Southern and Indian Oceans. Australia’s interior, however, is dominated by the endorheic Lake Eyre Basin.

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Meghan Modafferi, National Geographic Society
National Geographic Society
National Geographic Society
Last Updated

October 19, 2023

For information on user permissions, please read our Terms of Service. If you have questions about how to cite anything on our website in your project or classroom presentation, please contact your teacher. They will best know the preferred format. When you reach out to them, you will need the page title, URL, and the date you accessed the resource.


If a media asset is downloadable, a download button appears in the corner of the media viewer. If no button appears, you cannot download or save the media.


Text on this page is printable and can be used according to our Terms of Service.


Any interactives on this page can only be played while you are visiting our website. You cannot download interactives.

Related Resources