Wow was this an experience! I visited the Jinshanling section of the great wall. It is one of the sections that has not been entirely reconstructed. There were two things that struck me most about the great wall. The first was that it is literally on top of a mountain range. Just to cart the stones to the top of those mountains alone would have been quite the feet, let alone building a wall up there. A Chinese girl told me that there is a saying in China that the wall is built half from stone and half from bodies. I had never heard that before going to China, but I can completely understand it now. The second thing is that some parts of the wall are a lot steeper than i ever imagined, something like a 70% gradient at times. As I was climbing up the giant stones, melting in the heat, I wondered how on earth a soldier would have ever moved at any great speed along the wall. Guess that's why they had the fire signals. Thanks to the movie Mulan for that bit of Great Wall history....