My understanding has it that Disney built his backyard train system after seeing a similar one at the home his good friend, Disney animator, Ward Kimball. Kimball was a major railroad buff and he used to come to us at Em Gee Films with others from the San Bernardino Railroad society to get railroad oriented feature films of the silent and earily sound era for their annual event. I met Ward Kimball once in the late 1980s. As I recall from a Disney TV documentary, Walt Disney found the railroad in his backyard to be a great way to relax and enjoy the weekend.