 The Kottenforst is the southern part of a highland region that lies about 150 to , and known as the Ville, which drops steeply towards the east into the Rhine Valley, but whose western slopes descend more gradually towards the Swist and Erft rivers, forming a geological half-horst.The part of the natural region of Ville, which is not dominated by the brown coal mining of the Rhenish Brown Coal Field, is also called "Waldville".The Kottenforst is divided into a southeastern section between Meckenheim, Bad Godesberg and Bonn, into which areas of natural open country intrude in places, such as the Katzenlochbach Valley, and a northern area between Heimerzheim, Buschhoven and Alfter.