Incredible. The US is a much younger country, yes, but we've done a poor job of preserving the history we have. It's just a different mindset, really. With the help of LIDAR they're finding all kinds of indigenous settlements/earthenworks across the US that they previously didn't even know existed.

https://www.youtube.com/@CastlesandTiaras

I really like this YouTube channel. The host usually digs deep into the history of the properties she features.