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The Mutianyu Great Wall. The Mutianyu Great Wall is seated in the Huairou District, Beijing, 73 kilometers from the center of Beijing. Mutianyuguan was set up in 1404. The pass gate was built on a low, flat and open granite valley. The altitude differences of mountain peaks near the pass are no more than 100 meters. The construction of Mutianyuguan is very unique. The pass gate is composed of three hollow watch towers in parallel, the one in the middle was the biggest. On each watch tower there was built an originally designed watch pavilion. The pass gates were not set in the middle of the city platform, but at its two sides. The ramparts of the section are strong and the watch towers are grand and steep. The bottom of the rampart is generally 6-7 meters wide. The top is 4-5 meters wide. The height of the rampart is about 8 meters. The internal and external were all built with 13 layer granite slab outside.
The Mutianyu Great Wall was a complete and tight defense system composed by ramparts, watch towers, city passes, beacon towers and other buildings. The section goes westward from the Middle Pass Platform, along the mountain wandering to the summit, abruptly runs down to the mountainside, and suddenly ascends again. Since it is like a cattle horn, it is called ‘the Cattle Horn Edge’. The Arrow Buckle Great Wall is to its west that is 1044 meters above sea level. The Great Wall of the section was built on steep cliffs. The Great Wall and the mountain are most changeful and have beauty in rhyme. A lot of famous photographic works of the Great Wall have been taken there.