Located in Tempozan Harbor Village in Minato Ward, Osaka City, Kaiyukan is one of the world's largest aquariums, with a theme of biodiversity in the Pacific Ring of Fire that surrounds the Pacific Ocean. The biggest attraction is the huge "Pacific Ocean Tank" that sits in the center. The sight of the whale sharks swimming leisurely there is awe-inspiring, and it fascinates visitors. Around this tank, tanks representing various regions, such as the Japanese forest, the Aleutian Islands, and Monterey Bay, are arranged, and the unique display methods that recreate each ecosystem allow visitors to learn about the habitats of the diverse marine life on Earth.

In addition to whale sharks, Kaiyukan also exhibits many adorable and popular animals, such as sea otters, Pacific white-sided dolphins, penguins, and seals. Each tank is designed to allow visitors to observe the natural behavior of the creatures, and feeding times and commentary events are also held. Seeing the lively creatures will give you a real sense of the mystery and importance of marine life. It is a space of learning and excitement that everyone, from children to adults, can enjoy.

The building is set up like a large aquarium, and you can see various sea creatures from the top down.
There is no dolphin show.
At the end, there is an experience corner where you can touch rays and other creatures, which is popular with children.
At night, the building is transformed into a fantastical "night sea," and you can enjoy a romantic atmosphere that is different from the daytime. It is a rare time when sea creatures show off their nocturnal habits, and it is also a popular date spot.