Here in the US the right of way is private. If it's an active railroad, it's not safe.
I did map some old tracks here in Knoxville. They're not abandoned but dormant. I do urge people to be mindful that they could be wrong, though.
Whatever the case, it's slow going to walk the tracks. I didn't think of it before but it would be good to reach out railfans. They may be able to work with the local railroad, here in the US we have a loto of lightly used tourist lines, and get some pictures from the cab.