A drainage divide, water divide, divide, or watershed is the line that separates neighboring drainage basins. In flat country the divide may be invisible (just a notional line on the ground either side of which water starts its journey to different waterways). While, in hilly country, the divide lies along peaks and ridges. Drainage divides are important geographical, and sometimes political boundaries. Roads and railways often follow divides to minimize slopes and marshes and rivers.
There are three types of drainage divides: continental divide, major drainage divide, and minor drainage divide. A continental divide is a divide in which waters on each side of the continent flow to different oceans. A major drainage divide is a divide in which each side of the divide never meet again, although do flow into the same ocean. A minor drainage divide is a divide where water parts and eventually rejoins at the convergence of a river.
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