"Machu Picchu was clearly a place built for the effect of its surroundings and its relationship to the mountains around it," says Heaney. The twisting trail isn't the most direct route, but its heart-pounding ascents past other important ceremonial sites serve to build suspense for the final reveal - stepping out of the cloud forest to face the fabled mountaintop city.
The 27-mile (43-kilometer) Inca Trail, which modern travelers can still hike from the Sacred Valley to Machu Picchu, was originally designed as a pilgrim route that spiritually prepared the Inca for arrival at Machu Picchu. Pachacuti didn't intend Machu Picchu to become a large settlement, but to serve as a royal retreat and a pilgrimage site for the worship of Inti, the Incan sun god. Historians believe that Machu Picchu was constructed in the 1450s by the emperor Pachacuti, whose reign was marked by aggressive Incan imperial expansion beyond the valley of Cusco. "Machu Picchu is a spectacular site," says Christopher Heaney, assistant professor of Latin American history at Penn State University and author of " Cradle of Gold:The Story of Hiram Bingham, a Real-Life Indiana Jones, and the Search for Machu Picchu." "It embodies so much of what we think about Inca history in terms of architectural splendor and the science of empire building and agriculture. Since it was "rediscovered" by the American explorer Hiram Bingham in 1911, generations of travelers have marveled at its emerald-green terraced gardens and precision-crafted stonework framed by towering peaks above and the roaring Urubamba River below. Located 46 miles (75 kilometers) from the Incan capital Cusco in modern-day Peru, Machu Picchu is an abandoned cloud city nestled high in the Andes Mountains.