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 the site is often interpreted as "old mountain". Machu Picchu was built around 1450–1460. Its construction appears to date to the period of the two great Inca rulers, Pachacutec Inca Yupanqui (1438–71) and Túpac Inca Yupanqui (1472–93). There is a consensus among archaeologists that Pachacutec ordered the construction of the royal estate for himself, most likely after his successful military campaign. Though Machu Picchu is considered to be a "royal" estate, surprisingly, the estate would not have been passed down in the line of succession. It was only used for approximately 80 years before being abandoned seemingly due to destruction