The Longyou Caves. Discovered in 1992, no historical record or evidence of the work involved to excavate the almost million cubic meters of stone exists. The chiseling was done in such a way that it left a consistent pattern throughout the caves which some experts believe to be symbolic.There is also a rumor that seven of the caves have a distribution pattern that matches the seven stars of the Big Dipper.
Machu Picchu, Peru. The Inca were brilliant engineers and architects, carving and fitting interlocking stones together, without mortar, to help the structure flex during an earthquake, rather than crumble.