A while back I stumbled upon a YouTube channel called Desert Drifter. He hikes through the desert and showcases ancient cliff dwellings and other structures. It's oddly captivating.
Mesa Verde is one of those 'cliff dwellings' sort of places, near Cortez, CO. There's a plaque on the tour that describes the two cowboys who 'discovered' Mesa Verde in the 1860s, more or less. I often wonder what went thru those two guys heads, seeing a cliffside apartment house, more advanced than most anything they had seen built by Europeans, and which at that time had already been abandoned for 600 years.