Being around working steam trains... hearing the train honk, seeing the steam, and smelling the coal = happiness!
So, if you guessed Steamtown National Historic Site in Pennsylvania... then you were right.
Their is an amazing collection of all things trains. They have an incredible working turn table. You can ride a real restored steam train and passenger car. They have a TON of vintage train stuff to look at. They have a few restored train cars that you can walk through and touch (including a mail car).
I was seriously in fun overload!