An aviary is a large enclosure for confining birds. Unlike cages, 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.
The Saint Louis Zoo is home to the 1904 World's Fair Flight Cage. It is one of only two permanent structures built for the World's Fair which still remain (the other is the Saint Louis Art Museum's Cass Gilbert building). In 1904, it was the largest bird cage ever built. It remains one of the world's largest free-flight aviaries. The long, wide, and high cage was built specifically for the St. Louis World's Fair. Local pride in the giant cage motivated St. Louis to finally establish a zoo in 1910.
List of public aviaries
Home aviaries are popular with bird fanciers who have the space for them. Many bird breeders list themselves as "aviaries", since most bird pairs breed best in aviaries in contrast to breeding cages. The traditional home aviary is a do-it-yourself product, although these days sturdy, commercial aviaries are available to fit all spaces (indoor/outdoor), sizes and budgets.
There are two main subcategories of home aviaries: grounded aviaries and suspended aviaries. Grounded aviaries are affixed to the ground with a concrete base to prevent rats and other vermin from entering. Suspended aviaries are suspended in the air with only the 'legs' of the aviaries affixed to the ground; hence, the need for a protective base is eliminated in suspended aviaries. Most grounded aviaries typically feature a woodwork or PVC frame unlike the metal frame of public aviaries; however, it isn't uncommon for suspended aviaries to feature a metal frame.