Ostrach is a municipality in the district of Sigmaringen in Baden-Württemberg in Germany. Ostrach lies between the Danube and Lake Constance, about halfway between Sigmaringen and Ravensburg. It lies on the brook of the same name, which passes through a narrow pass between the glacial moraines left by the Rhine Glacier at the end of t…Ostrach is a municipality in the district of Sigmaringen in Baden-Württemberg in Germany. Ostrach lies between the Danube and Lake Constance, about halfway between Sigmaringen and Ravensburg. It lies on the brook of the same name, which passes through a narrow pass between the glacial moraines left by the Rhine Glacier at the end of the last ice age. The landscape is hilly and wooded. Abandoned quarries to the north and south of the village of Jettkofen have created small lakes.