Drainage divide

[3] In glaciated areas it often refers to a low point on a divide where it is possible to portage a canoe from one river system to another.

[7] 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.

Examples are Eben im Pongau, Kirchberg in Tirol and Waidring (In all of these, the village name indicates the pass and the watershed is even explicitly displayed in the coat of arms).

Extremely low divides with heights of less than two metres are found on the North German Plain within the Urstromtäler, for example, between Havel and Finow in the Eberswalde Urstromtal.

Since ridgelines are sometimes easy to see and agree about, drainage divides may form natural borders defining political boundaries, as with the Royal Proclamation of 1763 in British North America which coincided with the ridgeline of the Appalachian Mountains forming the Eastern Continental Divide that separated settled colonial lands in the east from Indian Territory to the west.