For example, as I'll discuss in a future blog entry, the parts of the Great Wall I was hiking on have been extensively "restored." What that means, as you will see shortly, is that I have no idea whether a single brick or stone of it is original. When I walked beyond the tourist section to where the wall had not been restored, it was a very different thing. A few brick outcroppings could be seen amid what could otherwise be mistaken for a long, overgrown hill of waist-high grass and shrubbery. To from that, to the "restored" section of the wall, must have been a task more of rebuilding than of restoring.
In other words, "historical preservation" in China has little to do with "preservation."
As I describe the places I visit, I'll try to indicate my best guess as to how authentic they are -- but of course this is only my guess, and I am by no means a professional historian.