Guida
Ashizuri Kaiteikan is an underwater observatory located within the Ryuguri Marine Park in Tosashimizu City, Kochi Prefecture. The observation room, situated approximately 7 meters below the sea surface, allows visitors to observe the surrounding rich marine ecosystem. The structure is characterized by a striking white cylindrical tower and a red observation deck protruding about 7 meters above the water, creating a unique architectural silhouette. The underwater observation room features 16 circular windows with 45mm thick tempered glass, providing an up-close view of coral reefs, tropical fish, and various marine life swimming by.
The facility opened on January 1, 1972. Historically, the original Shirahama Underwater Observation Tower was damaged in a tanker collision in 1985, leading to the construction of this current second-generation facility. The site is recognized for its architectural and cultural value and is designated as a Registered Tangible Cultural Property of Kochi Prefecture. Please note that starting from May 2026, the facility is scheduled to close temporarily to ensure safety due to the aging of the connecting bridge and to prepare for future increases in tourism demand. It has long played a vital role in preserving the local natural environment while serving as a key cultural resource.
The greatest highlight is the view from the underwater observation room. With 16 circular windows each 60cm in diameter, you can enjoy an unobstructed view of the world beneath the sea. Outside the windows, you will see vibrant tropical fish and larger migratory fish swimming among beautiful coral reefs. The architectural beauty is also a must-see: the 54-meter long connecting bridge leading from the shore to the tower, and the red cross-shaped observation deck above, add a distinct splash of color to the coastal landscape. The descent via the 64-step double helix staircase inside the tower is a unique experience that prepares you for the journey into the deep.
The clarity of the underwater view depends heavily on weather and light conditions. On sunny days, sunlight penetrates more easily into the water, making the colors of the coral and fish appear much more vivid; therefore, visiting during bright daylight hours is highly recommended. Additionally, since the types of fish in migration change with the seasons, you can enjoy different expressions of the sea depending on when you visit. Please be aware that the facility is scheduled to close starting May 1, 2026, due to bridge maintenance, so it is essential to check the latest operating status before your visit.
Here, you can experience the sensation of "walking underwater." The process of descending the double helix staircase to reach the world 7 meters below the surface feels like stepping into another dimension. Watching fish dart through the crevices of the coral reefs through the observation windows offers a profound sense of connection with nature. This site is also highly valuable for educational purposes, such as natural science studies or field research into marine biology.
Ashizuri Kaiteikan is located in the Ryuguri Marine Park area, characterized by a beautiful coastline. Nearby is the famous Cape Ashizuri, a scenic spot in Kochi known for its magnificent views of the vast Pacific Ocean. The surrounding coastline is ideal for nature observation and coastal walks. This area, where nature and architecture blend seamlessly, is an ideal destination for travelers seeking a peaceful and contemplative experience.
As this is a coastal facility, it is advisable to wear clothing suitable for changing weather. Since there are stairs involved in the descent, we recommend wearing comfortable walking shoes. Please observe proper etiquette to protect the natural environment; specifically, be careful not to scratch or damage the observation windows. Note that the facility is scheduled for closure after May 2026, so please verify the current operational status via the official website before traveling.