"Machu Picchu is a collection of Incan ruins in Peru. Until 1911, it was lost to the outside world--only the locals knew that a vast ancient city was hidden in the mountains. For decades, the only way to reach Machu Picchu was to hike for several days, which is why the Tomas saw it as an ideal place to hide the Clue. No one outside the branch knows if the Clue is still there today. The strict rule against flying over Machu Picchu could just be a coincidence. And Saladin might just be there to see if llamas taste like red snapper."