JinShanLing Great Wall, about 120 km from Beijing, lies in the mountainous area in RuanPing county, Hebei province. It was a key military stronghold. JinShanLing Great Wall was mainly built from 1570 during the Ming Dynasty.
The 20 km long Jinshanling Great Wall, although a bit smaller and narrower than Badaling and Mutianyu, features complicated and well preserved fortification systems. Jinshanling Great Wall meanders through fantastic natural scenery.
Jinshanling Great Wall is slightly in ruins and thereby has a special beauty. The wall is 7.8 meters high and 5 - 6 meters thick at the bottom. On the top, the wall is about 4 meters wide with 2 meters high parapets on each side. On the side facing the enemy were 2 meters high crenels called DuoKou. On the upper part of the DuoKou were large openings used to watch and shoot at attackers. On the lower part were small openings ('loopholes') through which defenders could also shoot while in greater safety from incoming fire.
In addition, there are 'obstacle-walls' built perpendicular to the parapets - a feature quite unique to Jinshanling Great Wall. These 'walls-within-walls' were used for defense against enemies who might have succeeded in scaling the wall.