Scott Alexander presents evidence against the existence of advanced Ice Age civilizations, particularly those rivaling ancient Egypt or 1700s Great Britain. Longer summary

Scott Alexander argues against the existence of advanced Ice Age civilizations, categorizing potential claims into three levels of advancement: Stonehenge-like, Egyptian-like, and 1700s Great Britain-like. He presents three main arguments: the lack of archaeological sites that would survive sea level rise, the absence of evidence for early crop and livestock domestication, and the lack of elevated lead levels in ice cores and human bones from that period. While he doesn't completely rule out Stonehenge-level civilizations, he finds strong evidence against more advanced societies. The post concludes with probability estimates for future discoveries of pre-11,000 BC structures at different levels of sophistication. Shorter summary