Watching the Grand Tour with DS - and there was a very long iron ore train in Mauritanea. People were riding on top of the iron.
Apparently it's a thing. Read a few blogs about people doing it - it's illegal but people do it.
A Practical Guide To Catching The Iron Ore Train In Mauritania (igoa-adventure.com)
I have ridden on the top of a bus before in Nepal. The locals were doing it - and I think that the idea was you could get off if the bus was likely to crash.
Has anyone else ridden on top of a train or bus?