Bollenberg - Geology and climate

Three hills compose the Bollenberg and the summit is 363 meters at its highest point. In the West part, the Marbach fault separates the Bollenberg from the Pfingsberg. In the North part, the Ohmbach fault separates the Bollenberg from its symmetrical hill the Strangenberg. The East and North-East gradient is composed by limestone, loess and marl deposit. The low precipitation (400 to 500 mm in a year) is due to the raging storms in summer which regulate the dryness. The Bollenberg is the driest calcareous hill in France.