In 1911 an American explorer came across an ancient city hidden high in the Andes Mountains of Peru. Since then, explorers, archaeologists, and tourists have been fascinated by this beautiful and mysterious city known as Machu Picchu. The city appears to have been carefully constructed—every stone is perfectly cut and placed. The Inca people built Machu Picchu at the height of their empire, but no one knows for sure how or why they created it. Read all about the myths and theories surrounding Machu Picchu and its history, as well as the science archaeologists are using to understand this ancient city.