“every some 60-80 years they would sacrifice whole cities by intentionally burning thousands of their houses. Then they would move to create another settlement.”
Hmmm. “Can’t we just get along?”
Sounds like one way to deal with the mortgage crisis......
“intentionally burning thousands of their houses.”
Perhaps this was a plan to exterminate vermin like rats, mice, fleas and lice. Supplemented with a good bath and plenty of nit picking, it could have been quite effective. If there was a disease epidemic they might have done this to appease the gods and discovered that it also eliminated disease for a time.
The circle design reminds me of similar marks carved into early celtic/british stone dwellings. Also the circle sites remind me a little of stonehenge.