Located at Osaka Port, this aquarium is known as one of the largest of its kind in the world. Take the Chuo Subway Line to Osaka Port Station, and you’ll see the striking exterior of the Kaiyukan just a five-minute walk away. From the outside, you can already spot the iconic whale shark statue swimming within the deep blue walls.
This aquarium is one of the most spectacular in Japan. Not only is its scale remarkable, but its uniqueness also sets it apart among aquariums worldwide. It recreates the Earth’s natural environment to the greatest extent, introducing the natural behaviors of various adorable marine creatures living in the Pacific Ring of Fire in the most understandable and nature-close way possible.
The aquarium is divided into 15 large tanks, starting with the “Japanese Forest,” which emerges above the water’s surface. Centered around the main tank — 9 meters deep, 34 meters long, and holding 5,400 tons of water — visitors can descend and experience the profound charm of this massive aquarium.
As you enter, the first thing you’ll see is the long underwater tunnel, where seawater surrounds you on three sides, allowing you to watch real schools of fish swim right by. This marks the beginning of a two-hour dreamlike underwater voyage.
As you continue walking, the ocean suddenly disappears, replaced by a small forest, accompanied by the sound of a gentle stream flowing through rocks. This is the “Japanese Forest” exhibit, showcasing the aquatic ecosystem of Japan’s forests and the streams that gather within rock crevices.
Turning a corner and heading downward, you’ll see the underwater section of the “Japanese Forest,” where you can observe the animals’ living conditions more clearly. It also illustrates how mountain streams flow and eventually reach the depths of the sea, ingeniously demonstrating the workings of a complete ecosystem.You can’t help but marvel at the ingenious design of the aquarium.
The next exhibit features the Aleutian Islands and Monterey Bay. These areas are divided into above-water and submerged sections, like cross-sections of the ocean, where you can see birds inhabiting the cold Aleutian Islands and seals swimming in Monterey Bay. I was lucky enough to catch the seal feeding time, and the interaction between the keeper and the seals was truly adorable.
All exhibits are thoughtfully labeled at the entrance, making it easy for visitors to learn about the habits of the animals and the natural characteristics of each zone. There are also stamp corners where you can collect unique travel stamps from each area.
As mentioned at the beginning, the aquarium houses the massive central tank holding 5,400 tons of water. The enormous whale shark swims slowly within it. Watching the fish drifting endlessly through time, it feels as if time itself has slowed, allowing for a spiritual connection with these underwater creatures.
I visited during the Christmas season, and there was a lively scene of Santa Claus under the sea greeting visitors along with the fish.
Besides the various fish swimming in the sea, I’d especially like to talk about a romantic encounter at the aquarium — the popular exhibit, Water Moon Galaxy.
Many aquariums have jellyfish exhibits, but at Osaka Aquarium Kaiyukan, the jellyfish transform into twinkling stars. The entire jellyfish hall resembles a miniature universe, with the jellyfish as scattered constellations across the Milky Way. Descending in the dimly lit elevator, you’re greeted by a sudden burst of light. Who could resist the beauty of starlight found only in the cosmos? Up close, each jellyfish boasts its own unique charm — translucent bodies suspended in crystal-clear water, exuding a serene beauty, with each tentacle quietly displaying the mystery and allure of life.
After experiencing the underwater starry sky, I’d like to introduce some special exhibits at Osaka Aquarium Kaiyukan — the sensory zones.
Passing through an icy corridor, you’ll arrive at one of the more unique areas of the aquarium. Here, the goal is to engage all your senses — smell, touch, hearing — not just sight — to experience marine life fully. The Antarctic Continent exhibit is about to undergo an update. What new surprises await us? We can’t wait to find out.
Observing penguins up close, you can even catch their distinct scent, with the temperature realistically recreated to match the region. There are also stingrays you can touch. Contrary to their dark, somewhat distant-looking skin, their touch is surprisingly soft, melting your heart with their adorable presence. Through these firsthand experiences with nature, we gain a deeper understanding of its importance to humanity.
Finally, there’s a shop full of cute plush toys and merchandise for everyone to choose from, plus the aquarium-exclusive ice cream in ocean-inspired colors. Don’t miss out if you’re passing by.
The Kaiyukan Light-up event continues until March 3rd. After visiting the aquarium, don’t rush off just yet. Take your time to slow down and admire this dreamy ocean created by the lights, as romance extends from the deep sea into the radiant night.