Unlike the Great Walls at Badaling and Mutianyu section, the Great Walls at Jinshaling, Simatai and Huanghua sections are very much untouched by tourists and crumbling very fast due to pollution. These walls are still of the original state with every brick originated to the early builders.
The 12 of us drove to Jinshanling section of the wall and hiked along the wall to the Simatai section. We had to camp overnight on the wall itself (something against the law actually, but since the nearest civilization is somewhere down the mountain slope, nobody really paid attention to us) because the journey was not very smooth.
It was an exhilarating expedition and anyone visiting Beijing, China, should try to hike there.