When my son was little, we utilized painters tape to make roads on the floor of our playroom. You can draw lines down the center with Sharpie as well as utilize your imagination.
Apparently sufficient parents have done this, that some clever toy market people decided to turn the diy approach into a product.
Playtape, which will run you about $12/roll on Amazon is a fantastic bit gift for a preschooler. It is available in a few varieties.
available on Amazon
There are train tracks, which seems helpful for travel if you want to just bring 3-4 trains as well as this roll of tape for your train addict, however I’m not sure any type of hardcore track enthusiast would be satisfied with this substitute. What do you think?
find railroad tape on Amazon
See also, Civil engineer tape.