I'm a big time rail fan. That is my second hobby next to cars. I had a model railroad setup but it's disassembled now due to a couple moves. Once I fix my house the way I want it, I'm going to dedicate a room for a room size model, prolly in H.O. scale because that is most affordable..
My favorites are first generation diesel. That scenic run they do at the royal gorge is first generation diesel powered.
Near the royal gorge are a lot of places to go white water rafting. The place is a playground.