http://www.mnsu.edu/emuseum/prehistory/latinamerica/south/sites/machu_picchu.htmlMachu Picchu are ancient ruins that were built in 1460 and 1470 A.D. They were built by Pachacuti Inca Yupanqui ,an Incan ruler. Most of the structure is made from granite blocks cut with bronze or stone tools, and smoothed with sand. The blocks fit together without any mortar and none of the blocks are the same size or shape. The blocks are so tight that the sharpest knife couldn't move them at all. All of the houses have steep roofs, with trapizoidal doors, and windows which are unusal. Some houses were two stories tall and the second storie had to be reached by a ladder.
