A valley floor divide is a low drainage divide that runs across a valley, sometimes created by deposition or stream capture.
Since ridgelines are relatively easy to see and agree about, drainage divides are often natural borders defining political boundaries, as with the 18th century North America Royal Proclamation of 1763 that preceded the American Revolution.
Drainage divides can be divided into three types:
A valley-floor divide occurs on the bottom of a valley and arises as a result of subsequent depositions, such as scree, in a valley through which a river originally flowed continuously.
Examples include the Kartitsch Saddle in the Gail valley in East Tyrol, which forms the watershed between the Drau and the Gail, and the divides in the Toblacher Feld between Innichen and Toblach in Italy, where the Drau empties into the Black Sea and the Rienz into the Adriatic.