The Rahden-Diepenau Geest (German: Rahden-Diepenauer Geest) is a natural region in the extreme northeast of North Rhine-Westphalia and in the neighbouring state of Lower Saxony in north Germany. It includes the overwhelmingly gently rolling geest between the Lübbecker Lößland to the south, the Diepholz Moor Depression to the north, the Middle Weser Valley to the east and the western Wiehen Hills and to the west. The Rahden-Diepenau Geest is part of the and thus belongs to the North German Plain, although they include foothills of the Central Uplands in the shape of the .