The attraction was conceived by Walt Disney, who drew inspiration from the ridable miniature Carolwood Pacific Railroad built in his backyard. The Disneyland Railroad opened to the public at Disneyland's grand opening on July 17, 1955. Since that time, multiple alterations have been made to its route, including the addition of two large dioramas in the late 1950s and mid-1960s. Several changes have been made to its rolling stock, including the conversion of one of its train cars into a parlor car in the mid-1970s, and the switch from diesel oil to biodiesel to fuel its locomotives in the late 2000s.