Feel Like You Are Walking Beneath the Ocean
The Shirahama Undersea Observation Tower is an all-weather observation tower approximately 18 meters high, with its underwater observation area located about 8 meters below the surface of the sea. Because the main attraction is underwater, visitors can enjoy observing marine life even when the weather is not ideal.
After entering the tower, visitors follow a spiral staircase downward toward the underwater observation chamber. As they descend, the sounds and atmosphere of the outside world gradually disappear, creating the strange sensation of being drawn into another world beneath the sea.
The underwater observation room has 12 round viewing windows. Through these windows, visitors can look directly into the natural waters surrounding Shirahama.
Unlike an aquarium, there are no artificial tanks separating visitors from the marine environment. The fish seen through the windows are living freely in their natural habitat. This makes the experience feel like an underwater walk, even for visitors who have never tried scuba diving or snorkeling.
Meet Marine Life Throughout the Year
The waters around the observation tower are home to approximately 30 species of fish throughout the year. Commonly observed species include black sea bream, Japanese rudderfish, and rockfish, which can often be seen swimming near the seabed.
Depending on the season, visitors may also encounter colorful tropical fish such as butterflyfish and blue damselfish. During the warmer months, visibility in the water can be particularly good, allowing visitors to enjoy the vibrant colors of the marine life.
Other fascinating creatures may also appear among the rocks. Visitors might spot a moray eel peeking out from a crevice or a lionfish gracefully drifting through the water.
Because this is a natural marine environment rather than an aquarium, the animals are not guaranteed to appear in exactly the same places every time. This element of surprise is part of the attraction. Each visit can offer a slightly different underwater scene.
A Unique Attraction with a Long History
The Shirahama Undersea Observation Tower first opened in January 1970 as what was described at the time as the world’s first undersea observation tower. When it opened, the concept of observing the ocean from an underwater tower was highly unusual and attracted considerable attention.
The original tower was later destroyed after a tanker collided with it during a typhoon. A second-generation tower was subsequently completed in 1988, and the attraction continues to be one of Shirahama’s distinctive sightseeing destinations.
The interior retains a somewhat nostalgic atmosphere that reminds visitors of Japan’s traditional resort culture from the Showa era. This retro character adds another layer of charm to the underwater experience.
Spectacular Views of the Pacific Ocean
The experience is not limited to the underwater observation room. The area around the tower also offers magnificent views across the Pacific Ocean.
Visitors can enjoy the contrast between the deep blue sea and expansive sky while feeling the refreshing ocean breeze. The scenery is especially beautiful around sunset, when the setting sun turns the surface of the ocean shades of orange and gold.
Watching the sunset over the Pacific while standing near the observation tower can be a memorable highlight of a trip to Shirahama.
Relax at SHIRAHAMA KEY TERRACE HOTEL SEAMORE
Next to the observation tower is SHIRAHAMA KEY TERRACE HOTEL SEAMORE, one of the major resort hotels in the Nanki-Shirahama area. The hotel offers a variety of facilities designed to help visitors enjoy the coastal atmosphere and Shirahama’s famous hot springs.
One of its most popular features is the Infinity Foot Bath. The approximately 30-meter-long foot bath creates the impression that the water extends directly toward the ocean. Guests can soak their feet while enjoying panoramic views of the Pacific, making it an ideal place to relax after sightseeing.
The hotel also features TETTI Bakery & Cafe, where visitors can enjoy freshly baked bread, as well as KON BAR, a relaxing evening spot for adults.
Other facilities include an infinity pool, barrel sauna, playroom, and bicycle rental service. Combining a visit to the observation tower with a stay at the hotel makes it possible to enjoy Shirahama as a relaxing seaside resort.
Explore Shirahama’s Famous Attractions Nearby
The area surrounding the Shirahama Undersea Observation Tower contains several of Wakayama’s most famous coastal attractions.
Senjojiki Rock Plateau
Senjojiki is a spectacular natural formation created by waves eroding layers of rock along the coast. The broad, flat rock surfaces resemble a huge tatami-mat floor, which is the origin of its name, meaning approximately “a thousand tatami mats.”
The area is also famous as a sunset viewing location, making it an excellent place to visit later in the day.
Sandanbeki Cliffs and Cave
Sandanbeki is a dramatic coastal landmark featuring towering cliffs overlooking the Pacific Ocean. Visitors can also explore Sandanbeki Cave, a sea-eroded cave located beneath the cliffs.
The combination of rugged cliffs, ocean waves, and the mysterious underground cave makes this one of the most impressive natural attractions in Shirahama.
Shirarahama Beach
Shirarahama Beach is one of the most famous beaches in Shirahama. Its bright white sand and beautiful emerald-green waters have made it a popular seaside destination for many years.
During summer, the beach becomes lively with visitors enjoying swimming, sunbathing, and other seaside activities. Its tropical appearance also makes it one of the most recognizable landscapes in the Nanki-Shirahama area.
How to Get to the Observation Tower
The Shirahama Undersea Observation Tower is easily accessible by public transportation. From Shirahama Station on the JR Kisei Main Line, take a Meiko Bus and get off at the Shin-Yuzaki bus stop. The observation tower is located just a short walk from the bus stop.
By car, the attraction is approximately 10 minutes from the Nanki-Shirahama Interchange on the Kisei Expressway. Its convenient location makes it easy to include in a sightseeing itinerary around Shirahama.
Discover Shirahama’s Underwater World
Shirahama Undersea Observation Tower “Coral Princess” offers a rare opportunity to experience the underwater world without diving or snorkeling. By simply walking down the tower’s spiral staircase, visitors can look through underwater windows and observe fish living freely in the natural sea.
The attraction combines the excitement of marine exploration with beautiful Pacific Ocean scenery, fascinating local history, and easy access to some of Shirahama’s most famous sights.
For international travelers, it is an especially interesting way to experience Japan’s coastline from a different perspective. Whether traveling with children, enjoying a romantic trip, or simply looking for an unusual attraction, Coral Princess provides a memorable glimpse beneath the waters of Shirahama.
When visiting Nanki-Shirahama, consider combining the underwater observation tower with Shirarahama Beach, Senjojiki, Sandanbeki, and the nearby hot spring resort facilities for a full day of coastal sightseeing and relaxation.