Shedd Aquarium (formally the John G. Shedd Aquarium) is an indoor public aquarium in Chicago, Illinois in the U.S.. It opened on May 30, 1930. The aquarium has more than 25,000 fish. It was the largest indoor aquarium in the world until the Georgia Aquarium opened in 2005. The aquarium holds 5,000,000 US gallons (19,000,000 l; 4,200,000 imp gal) of water. The Shedd Aquarium was the first inland aquarium with a permanent saltwater fish collection. It is surrounded by Museum Campus Chicago, which includes the Adler Planetarium and the Field Museum of Natural History.
The aquarium has 2 million annual visitors. It was the most visited aquarium in the U.S. in 2005. In 2007, it was the most popular cultural attraction in Chicago. It contains 1,500 species including fish, marine mammals, birds, snakes, amphibians, and insects. The aquarium received awards for best exhibit from the Association of Zoos and Aquariums (AZA) for Seahorse Symphony in 1999, Amazon Rising in 2001, and Wild Reef in 2004.