Steam and Early Locomotives

Rail locomotives built around a steam engine as the prime mover, from the first practical steam locomotives of the early nineteenth century through the mainline steam era that lasted into the mid twentieth century in most industrialized countries and later still elsewhere. Belongs here: any locomotive whose motive power is a steam engine, whatever its wheel arrangement, gauge or era. Does not belong here: diesel or electric locomotives, which replaced steam on most mainlines and are grouped separately, or the passenger cars and wagons a steam locomotive hauled, which are rolling stock rather than motive power.