Disneyland Park, originally Disneyland, is the first of two theme parks built at the Disneyland Resort in Anaheim, California, opened on July 17, 1955. It is the only theme park designed and built to completion under the direct supervision of Walt Disney.

Walt Disney came up with the concept of Disneyland after visiting various amusement parks with his daughters in the 1930s and 1940s. He initially envisioned building a tourist attraction adjacent to his studios in Burbank but after hiring a consultant to help him determine an appropriate site for his project, Disney bought a 160-acre (65 ha) site near Anaheim in 1953.

Construction began in 1954 and the park was unveiled during a special televised press event on the ABC Television Network on July 17, 1955.

Disneyland has a larger cumulative attendance than any other theme park in the world, with 726 million visits since it opened (as of December 2018). In 2018, the park had approximately 18.6 million visits, making it the second most visited amusement park in the world that year, behind only Magic Kingdom.

As of 2019, there are six Disney resorts in California, Florida, Tokyo, Paris, Hong Kong, and China with a total of twelve parks. They are Walt Disney World Resort (Florida) (Magic Kingdom, Hollywood Studios, Epcot, Animal Kingdom) and Disneyland Resort (California) (Disneyland, California Adventure).

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