Wheels are off a toy engine, axles mounted to wooden base covered in fancy foil and stabilized with dowels behind each wheel. (You could technically look under the cake from many angles and not see the dowels, which I wanted.) This was a very heavy, very time-intensive cake, but it was fun to finish. Millsap (the name on the bunker coat) is the baby's last name and it was his first birthday, so that's why it's Engine 1. :)