Roenthal is a twentieth century Swiss fortress, located in the canton of Aargau near the Swiss border with Germany. It was built between 1937 and 1939, overlooking the Rhine River and its purpose was to cross water to the hydroelectric power station in Dugern. It was part of the defense line on the Swiss border, and there is a museum that specializes in presenting a rich exhibition on the weapons and equipment of the Swiss army and foreign armed forces from the period of the first and second world wars.