A late friend had a model train hobby that had track running through tunnels in the walls from room to room. I live down the block from the Raleigh temple of model trains, Nick's Trains, which has a vast selection of scales and scenery, and few other hobby supplies. No trains for me, since we tend to "collect" things we don't intend to collect, but it is an amazing fantasy to see a good layout well maintained and operational. Like your little folks. Sprites from the tobacco tins no doubt.