Inca builders complete Machu Picchu, a citadel of stone above the clouds
Machu Picchu was completed around 1450 C.E., a royal retreat for the Inca ruler Pachacuti tucked high in the Peruvian Andes. Builders fit granite blocks so precisely no mortar was needed, and roughly 60 percent of the citadel lies underground as drainage. Spanish chroniclers never found it, and it stood quietly for nearly four centuries.









