The Stronghold (thriller) invites the boys to his house where in a big worry and hurry he tells them the story about Inca civilization, the ruins, which according to some historians were built by Incas, but which, however, could not be erected by Incas given their level of technology. The artist also tells them a legend about a lost city called Paititi, shows them a blurred photo of some unknown ruins in selva and gives them a handwritten map supposed to lead to that place. After some deliberations the guys decide to go to Peru and look for the Inca’s stronghold. Gunnar Ivers
Machu Picchu though his statements "were given no importance by the leading citizens." Only later did Bingham learn that Charles Wiener also heard of the ruins at Huayna Picchu and Machu Picchu, but was unable to reach them. Armed with this information the expedition went down the Urubamba River. En route Bingham asked local people to show them Inca ruins, especially any place described as having a white rock over a spring. At Mandor Pampa, Bingham asked farmer and innkeeper Melchor Arteaga if he knew of any nearby ruins. Arteaga said he knew of excellent ruins on the top of Huayna Picchu.