The 1954 concept illustration above, by Disney artist Bruce Bushman, shows Disneyland's King Arthur Carousel. One of Walt Disney's inspirations for Disneyland was watching his girls ride the merry-go-round at Griffith Park, so it's no surprise that a beautiful version of this classic ride would be one of the first attractions in his own park. The photo below (again courtesy Daveland) shows the King Arthur Carousel as it looked in March 1956, not long after Disneyland opened.
The carousel was hand-crafted in 1922 by the famous Dentzel Carousel Co. of Philadelphia. It was previously located in Sunnyside Beach Park in Toronto. Walt had it converted from a merry-go-round with many kinds of animals to a carousel with just horses, re-purposing many of the other animals over on the Casey Jr. Circus Train.