Machu Picchu Mysteries

Today i took a look into the historical, geographical and geological phenomenon known to us as Machu Picchu in Peru. Below is a 3D picture of the place from Google Earth. It is on a saddle like formation in the middle of a circular valley of the river... Urubamba surrounded by higher mountains, not far from Cusco or Cuzco, capital of the ancient Inka Empire that collapsed shortly before or @ the arrival of conquistadors from Spain, sometime around 1500.

From the first sight one could start thinking it is some sort of retreat or place of retirement for rulers in case or after a war and siege or occupation of the capital. In the video linked below there are also shown terraces that might be use for gardening that could provide some limited supplies for a number of people. Besides dwellings and terraces there are a few structures suggesting the place being strengthen for siege.

However there is something particular that distinguishes the site from the surrounding mountains. Northwestern side is so steep it is or could have been barren from vegetation for a height that exceeds many times the ideal height for defense purposes.

At present are two ways of access; one of them is an exhausting hiking trail and the other a recent road for modern vehicles.

Provided enemy troops in ancient times could get close enough to start climbing they would be exhausted at the end of the trail and easy to overcome by a much less numerous force. But what good would do in an invasion to conquer a place populated by 1000 people in the top of a mountain that cannot possibly do much to reverse the occupying of the nearby capital.

So that must have not been the purpose of the place.

From the beginning i've been lucky enough to find this video where it is shown a very interesting geological particularity. The area looking like a geological saddle where the ancient city is located is isolated geologically and mechanically from the rest of that structure by two... faults, and the appearance of it suggest a homogenous, solid, contiguous structure in the shape of a human front tooth that is capable of moving or oscillating separately from the surrounding mountains.

https://www.youtube.com/watch?v=daibulat2iw&feature=youtu.be&t=26m41s

For some reason, ancients always left behind clues about their doings though not so obvious for the tired occasional hikers or even conventionally thinking guides or even geologists.

There is in the middle of the so called Temple of Condor, in the middle of the city within a closed place used officially to sacrifice lamas, and that would have been normal during any celebration or party, a stone structure also resembling a human front tooth.

https://www.google.com/search?q=temple+machu+picchu+rock+pointed&source=lnms&tbm=isch#imgrc=CDbx1iLbz5gVoM:

What could all these mean. This area or section in the shape of a tooth in the geological saddle like structure, barren at one side is susceptible to being heated by the Sun in sunny afternoons (i hope again i'm not mistaken and is facing west). This most likely had been the cause for the geological fractures shown in the video, and also diurnal or Sun heat induced instability. If they could figure, by chance, that if somebody throwing a rock down inside a cave a the end of such a day could trigger a local earthquake, they could start and scary people in the valleys and blackmail them, triggering a sort of social avalanche surrounding and fed by fascination that could stay at the origin of building or exploiting an empire.

Don't know how deep this cave or tunnel in the picture linked below is, could it be deep enough to throw a stone ball through it? By choosing the shape, maybe of an egg and size of the rock could they possibly chose the frequency of vibration and seismic area where they would want to trigger one.

https://www.google.com/search?q=December+Solstice+Cave+machu+picchu&source=lnms&tbm=isch#imgrc=9-ImFU_cOkelbM: