Sonthofen is the most southerly town of Germany, located in the Oberallgäu region of the Bavarian Alps. Neighbouring Oberstdorf is situated 14 km farther south but is not classified as a town. Sonthofen is located at . In 2005, Sonthofen was awarded "Alpenstadt des Jahres" (Alpine city of the year).
In World War II Sonthofen was bombed twice because Adolf Hitler had built the Ordensburg Sonthofen where young boys were trained for service in Nazi Party organizations. The "Ordensburg" was not destroyed in the war and from 1946 to 1948 it was home to the United States Constabulary school and from 1956-2009 the German Bundeswehr located its Military Police (Feldjäger) and Staff Service School there. The German Army's NBC Defence School (ABC-Abwehr- und Selbstschutzschule) is located in another barracks in Sonthofen.