In Disney theme parks, the 'utilidor' system is a system of some of the world's largest utility tunnels, mainly for Walt Disney World's Magic Kingdom in Florida. The 'utilidors', short for utility corridors, are a part of Disney's backstage area. They allow Disney employees to perform park support operations, such as trash removal, and for costumed characters to quickly reach their destinations on the surface out of the sight of guests to avoid ruining the illusion that is being created.

They are built underground or above ground and also carry utility lines such as electricity, steam, water supply pipes, and sewer pipes.

These tunnels were first built for Magic Kingdom. Smaller 'utilidor' systems are built under the central section of Epcot's Future World, primarily beneath Spaceship Earth and Innoventions, and formerly at Pleasure Island. Disneyland, in California, also has a small utilidor system running throughout Tomorrowland.

According to modern legend, Walt Disney was bothered by the sight of a cowboy walking through California Disneyland's Tomorrowland en route to his post in Frontierland. He felt that such a sight was jarring, and detracted from the guest experience. Since the California Disneyland was small, such a tunnel system could not be feasibly implemented. When the new Florida Disney park was being planned, engineers designed 'utilidors' to keep park operations out of guests' sight.

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