Introduction to Laoniuwan Castle: Built in the third year of Chenghua in the Ming Dynasty (1467 AD), the Laoniuwan Castle is located on the cliffs close to the Yellow River Grand Canyon. It is a garrison castle for the Ming Dynasty defense system. , the Wanghe Tower at the north end of the castle is the overlook of the barracks. It is a masterpiece of Ming Dynasty architectural style and one of the symbols of Laoniuwan Scenic Area.