Jiankou (Chinese: 箭扣; pinyin: jian kou) is a section of the Great Wall of China. This section is a photographic hotspot due to its unique style, steep mountains and beautiful scenery. 'Jiankou', is translated as 'Arrow Nock' in English, for the shape of the mountain is like an arrow, with the collapsed ridge opening as its arrow nock.

Jiankou Great Wall located in the Huairou District 73 km north of Beijing. The Jiankou section of the Great Wall of China is located between the Mutianyu--ten kilometers to the east—and the Moshikou sections of the Great Wall of China. The Jiankou section of the wall was constructed in 1368 during the period of the Ming Dynasty. It is made of large white rocks which can be seen from a great distance.

http://en.wikipedia.org/wiki/Jiankou

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