Which Disney theme park opened in 1955?

The Disney theme park that opened in 1955 was Disneyland.

Disneyland opened in Anaheim, California, on July 17, 1955. It was the first theme park created and operated by the Walt Disney Company, and the only Disney park designed and built under Walt Disney's direct supervision. Walt envisioned a place where adults and children could enjoy attractions together.

Construction began in 1954 on a 160-acre site near Anaheim. The project was developed with the help of a creative team that later became associated with WED Enterprises, the precursor to Walt Disney Imagineering. Its original themed lands included Main Street, U.S.A., Adventureland, Frontierland, Fantasyland, and Tomorrowland.

The opening was accompanied by a nationally televised ABC event. Technical problems, heavy crowds, counterfeit tickets, and shortages led to the nickname “Black Sunday,” although the park soon became a major success. Tokyo Disneyland opened in 1983, Disneyland Paris in 1992, and Walt Disney World in Florida in 1971, so none of those is the 1955 answer.