Looks good! But like Rapture said, it's pretty big for a train...as in, very broad. I'd expect a train to be narrower. I mean, I don't exactly know how broad these old trains were compared to modern ones... I guess they might have been a bit more spacious. But I'm pretty sure they weren't spacious enough to drive through them with a horse carriage, which looks perfectly possible here!
On the other hand, it is one of the unwritten rules of level design after all, that you often have to make corridors and the like a bit wider than they would be in real life, because the player can't move with the same flexibility as he can in his real body... so it's up to you