[blam]

"This is exactly why human settlements have vanished in the past - they used up their water supply and had to leave."

The whole area became liveable only at the end of the Ice Age when the melting glaciers created river valleys. When the glaciers completely melted, the river valleys and lakes dried up...and,continue to do so to this day.

[TigerLikesRooster]

The sites of very ancient civilization have turned into dry/inhospitable lands a long time ago.

This Xinjiang/Central Asia, area around Liao River, ancient Hindu civilization site now in S. Pakistan, Sumerian sites, and ancient Egyptian sites(around Khufu's time)

Our ancient history is either buried in the desert/waste land(after Ice Age before 2000 BC) or under the water (during the Ice Age.)