The Viewliner Train was short-lived, appearing only in the 1958a map.
Walt Disney was a great fan of trains, to the point of having a small railroad that ran in his backyard. In addition to the steam locomotives that ran around the perimeter of the park, Disneyland had a small train, running around a bent figure eight track over the lagoon, which would one day host the submarine ride. The train was intended to show a modern conveyance, but was really a Chevrolet V-8 engine in a small aluminum-sided train. Ultimately, the concept of the sleek body of the Viewliner would be incorporated into the monorail, originally following a similar course over the lagoon and Autopia next door, before being extended to the Disneyland Hotel.
The Viewliner was removed in 1958 to make way for the monorail.