The “Mutianyu” section of the Great Wall of China. 🇨🇳 Although this photo has been taken on an angle, the wall is not flat. In fact, it is quite steep and undulating when just walking normally. Apparently they run a Marathon using quite a bit of the wall which, coupled with both the undulating slopes and the uneven cobblestones, would be extremely difficult and tough on the ankles, legs and body........
