Katsuura Undersea Park

Katsuura Undersea Park is a marine observation facility with a tower that descends 8 meters below the water surface. Large windows along the structure allow views of more than 90 different marine species living in the surrounding waters.

The facility opened in 1974 as a natural aquarium using the local coastal waters as its ecosystem. Its location was chosen to take advantage of the specific conditions of this marine area.

The facility displays fishing tools and shells from the area, connecting visitors to the long relationship between the town and the sea. These objects show how local people have worked with ocean life for generations.

The structure sits about 60 meters from shore and connects to land via a bridge, making entry straightforward. Be prepared for wet conditions on the bridge and weather that may affect visibility through the windows.

Two different ocean currents meet at this location, creating unusual combinations of sea life from different climate zones. Visitors may spot tropical fish alongside species normally found only in colder waters.

Location: Katsuura

Inception: June 1974

Website: http://katsuura.org

GPS coordinates: 35.13550,140.28478

Latest update: December 10, 2025 16:01