What fun things revolve around trains that an almost 2 year old would love?

My husband and I were thinking about visiting a train station or something because our son is enamored with them at the moment. He even has a Thomas the Train bed...and often insists on wearing his Thomas pj shirt as his real shirt. Are there any really cool train places in VA, DC, or NC that y'all know of? Somewhere that we could at least get a tour of one.