Its very hard to find anything in the lower 48 and Canada (Your right, Mexico has a lot more preserved sites) that are older that 400 years old. I was recently out in southern Utah and there are petroglyphs around Moab, some depicting horses which dates them to no earlier than the mid-1600s. Others are believed to be significantly older.
Meaning Ive seen something in the US that is older than your mum. /s
The Greeks invented sex, the Romans introduced it to women.