A Hot Spring So Wonderful You Forget to Leave
The name “Bokido” is said to have been given by Tokugawa Yorimichi, the 15th head of the Kishu branch of the Tokugawa family, who visited the area during the Taisho period (1912–1926).
While enjoying the hot spring and looking out over the magnificent scenery, Yorimichi was deeply impressed by the experience. According to tradition, he praised it as a hot spring so wonderful that one could “forget to go home.” This is said to have inspired the name Bokido, which expresses the idea of forgetting one’s return journey.
The name remains remarkably appropriate today. Once you settle into the warm water, listen to the waves, and gaze toward the endless ocean, it is easy to lose track of time.
A Giant Cave Created by Nature
Bokido is not an artificially constructed cave. The peninsula where Hotel Urashima stands was formed from geological layers that were once beneath the sea and were later uplifted by movements of the Earth’s crust.
Over a vast period of time, the powerful waves of the Kumano Sea repeatedly struck and eroded the exposed rock. This relentless natural process eventually created the enormous sea cave that visitors can see today.
A Vast Natural Space
The cave is approximately 25 meters wide, 50 meters deep, and 15 meters high. Entering the bath area, visitors are surrounded by towering natural rock walls and a massive cave ceiling.
Looking up at the rugged rock surfaces while soaking in the hot spring gives the impression of stepping into a world that existed long before modern civilization. The scale of the cave makes it easy to appreciate the immense power of the ocean and the geological forces that shaped the coastline of Kumano.
Spectacular Views of the Pacific Ocean
The greatest attraction of Bokido is the extraordinary view of the Pacific Ocean from inside the cave.
Through the large opening of the cave, the Kumano Sea stretches toward the horizon. At sunrise, the rising sun casts golden light across the water, creating a breathtaking scene. At sunset, the sky and sea turn shades of red and orange, while the cave and surrounding rocks form dramatic silhouettes.
After dark, moonlight may shimmer across the surface of the ocean, creating an entirely different atmosphere. At the same time, the sound of waves breaking against the rocks reverberates through the cave, reminding visitors that they are bathing inside a space created by the sea itself.
Few hot springs in Japan allow visitors to enjoy such an immense ocean landscape while bathing inside a natural cave. This combination of hot spring, ocean, and geological scenery is what makes Bokido truly special.
A Hot Spring with a Long Pilgrimage History
The history of Nanki-Katsuura Onsen, including the tradition of bathing in this area, can be traced back many centuries to the era of pilgrimage to Kumano.
During the Heian period (794–1185), aristocrats and members of the imperial family traveled long distances from Kyoto toward the sacred sites of Kumano Sanzan, the Three Grand Shrines of Kumano. It is said that travelers used the area’s hot springs to recover from the demanding journey.
The pilgrimage to Kumano became so popular that it was described as resembling a procession of ants, known in Japanese as “Ari no Kumano-mode,” or “the ants’ pilgrimage to Kumano.” Along the route, hot springs served not only as places to rest but also as locations for yugori, a traditional practice of cleansing the body before entering a sacred area.
The mysterious atmosphere of a natural sea cave such as Bokido would have offered an especially memorable place to rest and refresh oneself after traveling through the Kumano region.
Relax in Mineral-Rich Hot Spring Water
The water at Bokido is known for containing abundant sulfur and salt. Its distinctive bluish-white appearance and gentle sulfur aroma create the atmosphere traditionally associated with Japanese hot springs.
The water feels smooth against the skin, while its salt content is characteristic of a coastal hot spring. The mineral-rich water helps the body retain warmth, making it particularly pleasant after spending time outdoors.
Soaking in the warm water while listening to waves echo through the cave provides a peaceful escape from the pace of everyday life. It is an experience that combines the physical relaxation of an onsen with the soothing sounds and scenery of the ocean.
Explore the Hot Springs of Hotel Urashima
Hotel Urashima is known as one of Japan’s large-scale hot spring resorts, and Bokido is only one of several bathing facilities available to guests. Exploring the different baths is an enjoyable part of the stay.
Genbudo Cave Bath
Genbudo is another natural cave hot spring at Hotel Urashima. The rugged rock walls and sound of waves create a powerful atmosphere, allowing visitors to experience the mysterious relationship between the sea and the hot springs.
Taki-no-Yu
Taki-no-Yu is a hot spring where visitors can relax while listening to water flowing over natural rock formations. Its scenery and atmosphere evoke the feeling of bathing near a waterfall, adding a distinctive touch to the hot spring experience.
Hamayuu-no-Yu
Hamayuu-no-Yu takes its name from the hamayuu, or spider lily-like coastal flower commonly associated with the warm shores of southern Wakayama. The bath provides a comfortable setting for relaxing after a day of sightseeing.
Youhou-no-Yu
Located at a higher elevation, Youhou-no-Yu offers panoramic views over Nachi Mountains, Katsuura Bay, and the town of Katsuura. The scenery becomes particularly beautiful around sunset and after dark, when the lights of the surrounding area begin to appear.
Arrive by Boat Like Urashima Taro
Another memorable feature of Hotel Urashima is the journey to the hotel itself.
Guests can travel from Katsuura Port by a dedicated shuttle boat. The boat ride across the bay creates the feeling of embarking on an adventure to a mysterious island, with a playful connection to Urashima Taro, the famous Japanese folktale character who traveled to the Dragon Palace beneath the sea.
The views of Katsuura Bay and Kino-Matsushima from the boat are beautiful, making the short journey part of the sightseeing experience rather than simply a means of transportation.
More to Discover at Hotel Urashima
Hotel Urashima offers more than hot springs. The property includes a long escalator known as “Space Walker,” which connects areas with an elevation difference of approximately 77 meters. There are also observation areas and walking paths surrounded by natural scenery.
With so many places to explore, visitors can easily spend an entire day enjoying the resort and its surroundings.
A Signature Hot Spring of Nanki-Katsuura
Bokido is a truly special destination where several of the greatest attractions of southern Wakayama come together: a natural sea cave, a mineral-rich hot spring, spectacular Pacific Ocean views, and the long history of the Kumano pilgrimage.
Few bathing experiences can match the sensation of sitting in warm water deep inside a natural cave while waves crash against the rocks just outside. Sunrise, sunset, moonlight, and changing ocean conditions each create a different atmosphere.
If you are visiting Nanki-Katsuura, Bokido is a hot spring experience well worth seeking out. Take your time, listen to the waves echoing through the cave, and look out toward the Pacific. Just as its name suggests, you may find yourself forgetting all about the journey home.