From this perspective, it's hard to realize the scope of Machu Picchu. Although the ruins are at an altitude of 8000 feet, 3000 feet lower than Cuzco, they appear to be much higher, and definitely more isolated.
The isolated location, three days walk from Cuzco, and the rampant growth or rainforest in the region, kept Machu Picchu hidden for centuries, only to be "discovered" by Hiram Bingham in 1911.

So many questions are still unanswered about this city, its builders, purpose and function, and the ultimate abandonment that experts continue to study it and travelers visit in awe.