Today is National Train Day. As I've mentioned here before, I'm a train enthusiast. During my childhood, I spent many hours watching traffic on what was then the four track main line of the Pennsylvania Railroad, which passed my mother's home town, Tyrone, Pennsylvania. The 1950s were the era when U.S. railroads were replacing steam power with diesels, and I witnessed the last of steam power on the Pennsy. The clip above, courtesy of dcoursey82 and taken from Pentrex's "Pennsylvania Railroad Collection", gives a comprehensive overview of types of steam locos used by the "Standard Railroad of the World" in its heyday. I can remember seeing I-1s, J-1s, K-4s, L-1s, M-1s, and, on one occasion, a T-1.