An aviary is a large enclosure for confining birds. Unlike birdcages, aviaries allow birds a larger living space where they can fly; hence, aviaries are also sometimes known as flight cages. Aviaries often contain plants and shrubbery to simulate a natural environment.

Large aviaries are often found in the setting of a zoological garden (for example, the London Zoo, the National Zoo in Washington, D.C., and the San Diego Zoo). Spacious walk-in aviaries also exist in bird parks such as Jurong BirdPark in Singapore. Pittsburgh is home to the USA's National Aviary, perhaps the most prominent example in North America of an aviary not set inside a zoo. The Tracy Aviary is an example of a bird park within a public urban park, Liberty Park in Salt Lake City, Utah. Some public aquaria, such as the Oregon Coast Aquarium, Newport, Oregon, or the Monterey Bay Aquarium, have aquatic aviaries.

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