“The citadel of Machu Picchu was thus the third and perhaps most important jewel in the crown of architectural monuments that Pachacuti created."

 
An enormous “Nazca Line” as seen from the air on Peru’s SW desert coast; the Nazca civilization, known for its complex weavings, beautiful pottery, and the “Nazca Lines,” visible only from high above the ground, mysteriously collapsed around the middle of the first millennium, A.D.

Logging Caused Nazca Collapse 
BBC News
November 2, 2009
The ancient Nazca people of […]

 
 An Artist’s Reconstruction of the Pyramid Complex at Cahuachi, Peru
Ancient Peru Pyramid Spotted by Satellite
New remote-sensing technology reveals huge structure beneath surface
Discovery Channel
Mon., Oct. 6, 2008
A new remote sensing technology has peeled away layers of mud and rock near Peru’s Cahuachi desert to reveal an ancient adobe pyramid, Italian researchers announced on Friday at a […]