A divide is the highest ridge of terrain separating river basins. Divides can be relatively small and cover just a few dozen miles, or they can stretch thousands of miles. On either side of a divide, water drains into separate basins.
One of the most recognizable divide landforms in the United States is the Western Continental Divide. This ridge in the Rocky Mountains follows peaks in Montana, Idaho, Wyoming, Colorado and New Mexico. Snow melt, rivers, streams and lakes west of the Western Continental Divide empty into the Pacific Ocean. Water east of this boundary flows into the Hudson Bay in Canada or into the Gulf of Mexico.
The United States has more than one divide. The Northern Divide runs from Montana to Labrador in Canada. Water north of the divide goes to the Hudson Bay and the Arctic Ocean. South of this demarcation, water runs to the Gulf of Mexico. The Appalachian Mountains in the eastern United States separate water that flows into the Atlantic Ocean and the Gulf of Mexico.
A unique spot known as a triple point exists where two continental divides meet and water flows into three separate watersheds. Five such places are found in the United States. One of these triple points is aptly named Triple Divide Peak in Glacier National Park, Montana.