As we enter June, Japan’s rainy season (known as tsuyu), has arrived in the Kansai region. While rainy days might make you hesitant to step outside, Osaka offers plenty of wonderful spots that can be enjoyed regardless of the weather. Today, we would like to introduce a popular place in Osaka: Kaiyukan, one of the world’s largest aquariums. Featuring an enormous whale shark, mesmerizing jellyfish exhibits, and an atmosphere that transforms into something enchanting at night, it is the perfect place to unwind after work or on the weekend—especially during this rainy season.
1. Encounter the World’s Largest Fish at Kaiyukan
Located in Tempozan within the Osaka Bay Area, Kaiyukan is one of the city’s most iconic attractions. Because Kaiyukan is entirely indoors, you can take your time and explore without worrying about the weather, making it an ideal destination during the rainy season. The access via train is very convenient, being just a 5-minute walk from Osakako Station on the Osaka Metro Chuo Line.
- Must-See Highlight: One of Kaiyukan’s biggest highlights is the whale shark swimming in the massive “Pacific Ocean” tank. Only three aquariums in Japan feature permanent whale shark exhibits: Kaiyukan (Osaka), Okinawa Churaumi Aquarium (Okinawa), and Io World Kagoshima Aquarium (Kagoshima). Being able to see these magnificent creatures up close right here in Osaka is a truly special experience.
- A Dreamlike Atmosphere: With fish swimming peacefully overhead, soft blue light filtering through the water, and the gentle ambiance of the jellyfish exhibits, it is easy to lose track of time. Simply watching the giant whale shark glide gracefully through the water is a mesmerizing experience.
2. “Night Kaiyukan”: A Mystical Nighttime Experience
Did you know that Kaiyukan also offers a “Night Aquarium” experience, featuring a completely different atmosphere from during the day? After 5:00 PM, the lighting and music inside the facility shift, transforming it into a tranquil and enchanting space.
- Why It’s Special: You can watch the sea creatures glide peacefully through the water in soft, moonlight-like illumination. The massive “Pacific Ocean” tank and the jellyfish area, in particular, take on an even more mystical atmosphere at night. Gazing at the whale shark in the quiet aquarium makes you feel as though time has slowed down.
▶ Explore the Bay Area Around Kaiyukan!
On a sunny day, after immersing yourself in the relaxing underwater world, we highly recommend visiting the adjacent Tempozan Giant Ferris Wheel, one of the largest Ferris wheels in Japan. Located right along Osaka Bay, it is a popular attraction that offers expansive coastal views during the day and a stunning cityscape at night.
- See-Through Cabins: If you are not afraid of heights, the “See-Through Cabins”—which feature transparent seats and floors—are a must-try. They provide a 360-degree panoramic view beneath your feet, making you feel as if you are floating in the sky.
- Beautiful Panoramic Night Views: The Tempozan Giant Ferris Wheel is recognized as a “Facility-Type Night View Heritage” site under the Japan Night View Heritage program. In addition to sweeping panoramas stretching from Osaka Bay to the Umeda and Kobe areas, the stunning LED illuminations on the wheel itself are another major highlight.
Closing Thoughts
It is easy to stay cooped up indoors during the rainy season, but there are wonderful places to explore just a short trip away. Finding comfort and tranquility in a quiet underwater world—such a relaxing and casual weekend outing might be just what you need to enrich your daily life. This June, why not visit Kaiyukan and experience another unique side of Osaka during this rainy season?
