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metropolis

An illustration of North America's first city, Cahokia.

The Rise and Fall of Cahokia: Did Megafloods Spell the End of the Ancient Metropolis?

The mysterious demise of the ancient city of Cahokia has long remained unexplained, but now research suggests catastrophic megafloods may have devastated crops and food stores, and forced residents...
Mohenjo Daro

Experts say Mohenjodaro may disappear in 20 years

When the ancient ruins of Mohenjo Daro (which means Mound of the Dead) were first uncovered in Pakistan in 1922, its significance was not fully realised. Dating back 5,000 years, Mohenjo Daro is the...