The Seattle Aquarium opened on May 20, 1977, on Piers 59 and 60 along the downtown Elliott Bay waterfront. Managed by the nonprofit Seattle Aquarium Society since 2010 and accredited by the Association of Zoos and Aquariums since March 2024, it now draws roughly 850,000 visitors a year, ranking among the most-visited aquariums in the United States.
In August 2024 the aquarium’s footprint expanded dramatically with the debut of the Ocean Pavilion, a 50,000-square-foot building anchored by The Reef, a habitat holding nearly 500,000 gallons of water and recreating Indonesia’s Coral Triangle. The new wing sits alongside the original Pier 59/60 galleries, which focus on the cold, nutrient-rich waters of Puget Sound and the greater Pacific Northwest.
Stats at a Glance
- Location: Piers 59 & 60, 1483 Alaskan Way, Seattle, Washington
- Opened: May 20, 1977
- Size: Ocean Pavilion: 50,000 sq ft with a nearly 500,000-gallon Reef habitat; original site includes a 400,000-gallon Underwater Dome
- Species: Nearly 400 species
- Animal count: Over 12,000 individual animals
- Annual visitors: About 850,000
- Famous for: Giant Pacific octopuses and the Coral Triangle sharks and rays of the Ocean Pavilion
From Pier 59 to the Ocean Pavilion
The Seattle Aquarium began as a Pier 59 attraction built for about $5.4 million, opening to the public in 1977. The City of Seattle handed day-to-day operations to the nonprofit Seattle Aquarium Society in 2010 under a long-term agreement, and the facility earned AZA accreditation in March 2024.
The biggest change in the aquarium’s history came on August 29, 2024, with the opening of the Ocean Pavilion, an approximately $160 million expansion that nearly doubled the campus and introduced the aquarium’s first major exhibit dedicated to a tropical marine ecosystem.
Exhibits and Conservation
Signature exhibits include the 400,000-gallon Underwater Dome, the Window on Washington Waters dive-show tank, a dedicated Giant Pacific octopus habitat, and the open-air Birds and Shores exhibit featuring puffins and auklets. The Ocean Pavilion’s Reef habitat, nearly 500,000 gallons, added sharks, rays, and reef fish representing the biodiverse waters of Indonesia.
The aquarium is also active in conservation work, including participation in the ReShark program, which has released zebra shark pups into Indonesian waters as part of a regional species-recovery effort.
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Seattle Aquarium FAQs
When did the Seattle Aquarium open?
The Seattle Aquarium opened on May 20, 1977, on Piers 59 and 60 along Seattle’s downtown waterfront.
How many species live at the Seattle Aquarium?
The aquarium is home to nearly 400 species and more than 12,000 individual animals.
What is the Ocean Pavilion?
The Ocean Pavilion is a 50,000-square-foot expansion that opened in August 2024, featuring The Reef, a habitat holding nearly 500,000 gallons of water and modeled on Indonesia’s Coral Triangle ecosystem.
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Photo: Joe Mabel / CC BY-SA 3.0, via Wikimedia Commons.