beijing - a panoramic view on an unrenewed gubeikou part of great wall of china. the wall is spreading on tops of mountains

china great wall brick window overgrown grass hills nature mist fog smoke pollution smog watch tower world heritage site stone gubeikou chinese beijing mongolia greatwall simatai outdoors jinshanling dynasty tourism mountain landmark architecture history ancient hill landscape scenic travel monument culture province ruin mountains scenery asia sightseeing watchtower outdoor