color colour image indoor square photography museum ancient army terracotta numbered destroy "unesco world heritage" damaged shaanxi xi'an lintong "mausoleum of the first qin emperor" "pit 3" "qin dynasty" "unesco world heritage site" "terracotta warriors" history discovery archeology "place of interest" ruined broken buried tomb antiquities "travel destination" site" "terracotta warriors" history discovery archeology "place of interest" ruined broken buried tomb antiquities "travel destination" - Alamy