I have built an L shaped layout, that is 30" deep and 18 feet long before it turns and goes 4 more feet. The ends are both 48" to accomidate a 22" radius turnaround. I have been operating on other layouts for about 4 months now. My problem however is how to make my own layout into a operational layout. I have thought of making somewhat of a double decker for part of the 18 feet to try and increase the mainling run time. Is that a good idea? Also I'm not sure how to incorporate things like interchanges. I'm alos wondering if I have a coal mine to pick up cars, what sort of area do I drop the cars at? Any help would be greatly appreciated.