Cologne Lowland

The Cologne Lowland, also called the Cologne Bay or, less commonly, the Cologne Bight (German: Kölner Bucht, pronounced [ˈkœlnɐ ˈbʊxt] ), is a densely populated area of Germany lying between the cities of Bonn, Aachen, and Düsseldorf/Neuss. It is situated in the southwest of the state of North Rhine-Westphalia and forms the natural southern conclusion of the Lower Rhenish lowlands and the transition to the Rhenish Massif (Rheinische Schiefergebirge or "Rhenish Slate Mountains").

The Cologne Bight is surrounded by the High Fens and the Eifel to the west of the Rhine and by the uplands of Bergisches Land to the east of the Rhine. In the south and southeast the rising Rhine Massif, visible from far off by the silhouette of the Siebengebirge, surround the head of the bight at Königswinter.