Dachau concentration camp was the first of the Nazi concentration camps opened in Germany, intended to hold political prisoners. It is located on the grounds of an abandoned munitions factory northeast of the medieval town of Dachau, about 16 km (10 mi) northwest of Munich in the state of Bavaria, in southern Germany. Opened in 1933 by Heinrich Himmler, its purpose was enlarged to include forced labor, and eventually, the imprisonment of Jews, German and Austrian criminals, and eventually foreign nationals from countries that Germany occupied or invaded. The Dachau camp system grew to include nearly 100 sub-camps, which were mostly work camps or Arbeitskommandos, and were located throughout southern Germany and Austria. The camps were liberated by U.S. forces on 29 April 1945.