Visitations long ago?

This isnt really an opinion more of a subject to anyone who might be interested. Ive been really interested in mysteries on a broader scale for a long time and i have been especially interested in a place called Tiahuanaco. I know this probably isnt linked to UFO's but its a weird place in its own right.

To cut a long story short it is basically an ancient collection of monuments in Bolivia. Boring i know but i got a little bit more curious when i found that this place was up to 15,000 years old! One of the oldest man made structures in the world. Further more the technology needed to build this place was immense. Huge stone structures were placed together like jig saws with welding and metal nails. The cuts performed on the rocks are literatly like laser precision cuts. Have a look yourself? Pretty incredible stuff. All this thousands of years before even the pyramids!

It is also thought the place was more of a meeting point not a city for what reason i dont know. The culture of the people visiting is also a bit weird. Maybe have a read up for yourselves! Im not suggesting anything Alien, but it does make you wonder.