If you are around South America, stop at this world wonder and see it with your own eyes. It was amazing to get to the hidden Machu Picchu in the midst of the Andes mountains. Solid 4 hours walking around the mountain up and down the terraces and through the stone-carved buildings. It was interesting to see how Incas built Machu Picchu in the 15th century, by carrying 50ton stones up the steep cliffs and carving them into buildings, temples, baths and terraces. How on earth did they do this? No Idea- it was mind-boggling to try to figure out.