Mutianyu Great Wall is located in Huairou district, Beijing. To the west of Mutianyu is Juyongguan Great Wall, while to the north is Gubeikou. Since ancient times, this has been a location with military significance and has defended Beijing from attack. Mutianyu Great Wall is principally built on the edge of a steep hill, using the hillside as an advantage. The height of the Great Wall reaches seven to eight meters and the width reaches four to five meters. The main building material is granite, making the structure both majestic and solid. There are many towers on the Mutianyu section. There are 22 towers on the currently open section, which is 2250 meters long.