My first trip overseas was to the UK, during university, as a term abroad kind of thing. One night, some of my peers and I went round the pub, and I got to talking with an older local. I commented that it was a strange and perspective-shifting thing to be around human structures so old, "which we don't have back in the States".

He offered the counterpoint of, e.g., Chaco Canyon as something even older.

Time is indeed relative. That kind of perspective-check is awesome.