Scholars are still striving to uncover clues to the mysteries of engineering marvel Machu Picchu—in the meantime it continues to marvel visitors the world over http://on.natgeo.com/2A6KXvY

Scholars are still striving to uncover clues to the mysteries of engineering marvel Machu Picchu—in the meantime it continues to marvel visitors the world over http://on.natgeo.com/2A6KXvY 

https://twitter.com/NatGeoTravel/status/933742089812283392