Ever since the History channel was pressured by market forces into abandoning history altogether, one of its most popular shows has been the pseudoscientific documentary series Ancient Aliens. The show follows in the footsteps of more than a century of science fiction writers who have proposed that many feats of ancient engineering were impossible with contemporaneous technology. A number of their theories began with one man: the Swiss author Erich von Däniken, author of more than 20 books — the earliest in 1968, the most recent in 2021 — questioning humanistic explanations for megalithic structures around the world.

Now, from Egypt to Easter Island, believers in “ancient aliens” claim that countless structures are earthbound evidence of extraterrestrial visitation. Such claims are obviously controversial — not only because there is no evidence of aliens existing, let alone visiting Earth, but because many of the buildings credited to these aliens are the handiwork of civilizations plenty of Americans could do with learning about.