idk - I've heard various reports stating that the Aliens built the tunnels as their habitat bc they can not function w/out genetic engineering in our atmosphere, oxygen and sunlight, hence the tunnels. They have been mining minerals in the tunnels and feed on humans -- using their technology as bribes. (a.I., black goo, med beds, levitation) Gene Decode / Kerry Cassidy / Phil Schneider / Dr. Salla / Secret Space Program "20 and Back" and it seems to be a consensus of opinion ... Its a logical course for the development of this satanic order / honey pots / andrenochrome.

Yes, you are right, this is possible of course. I´ve heard the same things too often but only opinions without any evidence, right? So, the rabbit hole goes deep and deeper probably.

It is said, that the hidden history of Skythia/Tartaria (--> worldwide connected ancient electromagnetic water power grid hundreds of years old built from unearthly creatures) the real hidden history in the world is bc it leads to god (frequency, vibration, energizing the aether/water, levitating and all this stuff...). In fact, you see it everywhere. Let´s see, what else we can find out. The deception is tremendous.

wasn't the hanging gardens of babylon a result of tunnel water irrigation?

I don´t know it for sure, but if the story of Great Tartaria is really true, babylon is - or what we know as babylon - fiction.