[GeronL]

If a large group of vilunteers, archaeologists, students and interested people did it like a wiki project I think it could work.

[muawiyah]

I've found signs of an underlying survey that had to have been done for most of North America EAST of the Rockies ~ this is long before the Brits took over Canada.

There are definitely some Spanish town sites at the intersections of primary lines of longitude and latitude ~ with the sort of error in longitude you'd find before the development of really great watches ~ even found signs of some surveying being done with magnetic compass (always a loser BTW)

Might be possible to organize something like SETI. Or, call it Search For Ancient Hombres

About the Law of the Indies, South America and Mexico have a great number of towns laid out according to the Spanish law for a new settlement, so there's little doubt about what you're looking at when you find it.

In what is now the United States and Canada early settlers have pretty much done their own idiosyncratic layouts, so the Spanish towns STAND OUT ~ although there are some French towns that can cloud the issue.