[watchfirst9]

Yea one thing I always feel How we human been form I even feel we are “ alien project “

Look foetus how it form etc is a thing
Etc the human/ animals 
Remember we also animals but in the sense we think differently etc than other animals

All animals like us cannot live forever
All theses surely someone something create


I always view a pet fish like us human in the tank aka is earth and alien is monitoring how we evolve.

If you check out various ancient buildings around the world is something hard to explain etc yet they have some similar.

Nothing can be confirmed so far. 
One thing for sure, there are highly advanced society before last ice age.

The structure is incredible heavy and expensive for current technologies.