Brien Foerster - author, biologist & resident explorer of Peru breaks down the following in this interview:

• Cusco’s megalithic origins
• Oral traditions that state the Inca found Cusco’s megaliths when they arrived to the area
• Napa Huaca, a remote mountainous cave featuring precision cut megaliths
• The strange elongated skulls of Peru
• The Nazca Lines
  

Also mentioned in this episode:

• Peru's 7 Strangest Elongated Skulls
• The Wormhole of Inishmore