Not all arcaeological sites involve petroglyphs or Indian ruins - or even Indians. In 2009, we "found" the L'Anse aux Meadows site (by driving an extra 500 miles) to the northern end of Newfoundland. I was skeptical until I got there and learned about it. But then I'm naturally skeptical.
L'Anse aux Meadows is located on the northern end of Newfoundland and is the only authenticated Viking site in North America. The Vikings visited several times around 1000 AD. They tried to establish a colony here, but ran into trouble with the Inuit and eventually withdrew.
It's known that this was not the only place they landed in North America, but the location of the other site(s) are unknown. Or at least, have yet to be found.