The gridded, cobblestoned town streets are the product of Inca city planning, dating back to the 1200s.

BBC: Walking in Inca footsteps in Peru's Sacred Valley

He goes on to list some of the stand-outs of the 1200s.

FORBES: Rick Santorum and the 13th Century

The Incan state didn't emerge until the 1200s.

CNN: 10 things to know before visiting Peru