The Kyffhäuser Mountains at the border to Saxony-Anhalt extend for 13 miles (21 km) and reach a maximum height in the Kulpen-Berg (1,565 feet [477 m]). Legend has it that Frederick Barbarossa, the red-bearded king who, with his army was killed in his attempt to cross the river to meet his enemy is waiting with his six knights in a cave in the mountains. When the time is ripe for the doing of mighty deeds, he will return and free Germany from oppression.