Praga Welding Truck, Obchodni Dum Petriny, Prague, CZ, 2007

DPP have a fleet of these 60-some-odd-year-old Praga trucks for trackwork, which only started getting replaced by modern Mercedes equivalents in the past few months. They mostly carry tools, and in addition most (maybe all, I don't know) of them have a very large and I assume powerful arc welder on board, as do the new Mercedes. These might be, in fact, some of the oldest trucks used by any transit authority in the developed world. Can anybody think of anything older?