Hidden at the end of a long ravine, the buildings of Petra, Jordan, were carved into sandstone cliffs by the Nabataeans around 312 B.C.

• 这是约旦的佩特拉，隐藏在一段狭长峡谷的尽头处，这建筑是在公元前312年由纳巴泰人在沙岩悬崖上雕刻建造而成。