Machu Picchu was built around about 1450 AD, atop a high granite mountain on a high ridge encircled by several other mountains. The skilfully crafted stonework and layout of the city attest to the architectural ingenuity and skills of the Inca peoples who planned and built their city complex by integrating it into the rock escarpments on which it is built. The buildings follow the contours of the steep mountain slopes, whilst the terraces, ramps and plaza areas have been carved into the steep mountainous terrain, forming new contours to create level areas for grazing animals and growing crops. The ingenious Inca builders even included an extensive water-distribution system throughout the whole complex to prevent flooding of the homes, fields and plazas. Some of the water was channelled to the 16 stone fountains cleverly built in descending elevation throughout the site
As we mentioned earlier the size of Machu Picchu is massive and whilst we only had time to see a portion of it, what we saw was amazing. Historians agree that from the number of buildings and the infra structure that at least 750 people lived here within the walls of this stronghold city. At religious festival and harvest times the numbers could have swelled to over 50 thousand.
A huge portion of the city has been restored but much of its semi-intact infrastructure remains a ruin that we could rebuild in our imaginations, because the 'bones of the city' are in place.
There are no written records about the purpose of this archaeological site, perched in such a remote mountainous area but historians generally agree that Machu Picchu was probably one of the many royal estates around the country. The number of temples, fountains, and sacred rock s and burial areas suggests that it was also an important ceremonial site. Our guide, Jamie speculated the vast number of terraced areas (once advanced agricultural plots) which stretch up, down and across the steepest of slopes and many stone granaries suggests that Machu Picchu may have grow high-altitude potato, corn and coca crops.
Entering under the huge stone lintel of the Main Entrance Gate we could not but be impressed with the workmanship of the Inca masons. Each stone chosen to fit perfectly in place like a piece in a jig-saw. Stone blocks manoeuvred to and handled by men to form strong walls held together not with mortar but by physics. True engineering artisans had built these impressive structures that time has not completely destroyed. Take a look at the size of the stone blocks used around and above the main entrance gate and be impressed, as we were!
The thickness of some of the walls is amazing and would have provided refuge from the long winter nights and strong gales from the winds that blast the mountaintops when the weather is wild. 
Having entered the main entrance gate we began our walk through the initial section of the ruins, on a narrow path past what may have been the homes of the builders and their families. Touching the ancient stonework, we tried to imagine what living here would have been like. If only these stones could talk, we could learn so much more about the Inca community life. At the end of this first corridor passageway the pathway opened out with several choices of either ancient stairs or dirt paths all connected to the different regions of the city. But immediately in front of us was our first panoramic view over the Inca city ruins. Look at the photo of Ken with his hands raised high in the air. He has a look of exhilaration on his face, which says it all. "Here at last, Eureka!"