It got sidetracked by the submitter themselves by mislabeling it as “Google Maps of Roman Roads”.

How come nobody ever cares to disambiguate vendors? Or perhaps they do...

And yes, let me overstate it - Google is not part of anything related to this research, and for their valuable contribution, overall and in particular, they are very kindly not mentioned in the paper.

But guys here don't care about peculiar details, no?

Interestingly, the interesting (pun intended) topic did not rise the very obvious question - is the data open. Well, idk, but is at least downloadable.