Railnauts—that's a good word for brothers Ivan Puig and Andres Padillas Domene. After Mexico privatized its rail system in 1995, around 6000 miles of track have gone unused. They wanted to explore them, so they built a custom vehicle for the task.
The Manned Railway Exploration Probe, in addition to having an excellent name, is the result of their efforts. It started out as an old pickup, which they rebodied in aluminum and converted into a road-rail vehicle they could use to drive to any site and mount to the rail line.
It was their home base for their two-year journey, which they discuss in the video above.