 To the east of Stein , 2 kilometers ( 1 @.@ 2 mi ) down an old road , lay <unk> , with its small population of a few hundred , at the confluence of the stream of that name and the <unk> . To the west of Stein the <unk> made a large curve , creating a crescent @-@ shaped floodplain between it and the mountains . At the far western end of the floodplain , where the mountains came down almost to the river 's edge , was <unk> with its castle , known as <unk> <unk> . The castle had served as a prison for Richard I of England in <unk> . In 1645 – 46 , during the Thirty Years War , the Swedes had fortified the castle and then demolished it when they withdrew . It stands at 159 meters ( 522 ft ) , on the highest ridge of a mountain <unk> with <unk> and pinnacles of granite . Because the mountain was sparsely <unk> , it was difficult to distinguish the ruins from the rocks . <unk> canyons cut through the mountain , and widen into the plain below . Between <unk> and Stein , on the flood plain , lay the hamlets of <unk> and <unk> . Near the hamlets , the <unk> flood plain was at its <unk> , extending at the most 762 meters ( 2 @,@ 500 ft ) from the base of the <unk> mountain to the bank of the river . 
