From the White Jurassic to the Muschelkalk the Starzel passes through all layers of the Jurassic and about two thirds of the Triassic. Its valley was formed by retrograde Erosion, in that the stream from the northwest cut deeper and deeper into the strata of the Swabian Alb and its foreland. The valley of the Starzel river intervenes eleven kilometres into the plateau of the Swabian Alb and is bordered in the west by the 957 high Raichberg and in the east by the up to 840 meter high hayfield. It begins with the source area of the Starzel and its tributaries at the watershed between the river system of the Rhine and that of the Danube.