Suspension Railway

This is a large project designed for FDM printing, no supports needed. The tallest point of the structure is 65cm. 

With the rails and legs you can build as long a structure as you want. I recommend adding a leg after every third normal rail. This way the weight won't strain the structure too much. The legs can fit on a 12 inch square, following my recommendations both legs will fall in the middle of the two outside squares on a 3 feet by 3 feet playing area. 

Dont let the size intimidate you tho, I put in a lot of effort to streamline the building and printing experience so it's really straightforward.