Kuroshima and the Legends of the Kumano Suigun
An Island Associated with Maritime Warriors
Kuroshima is traditionally said to have been one of the bases of the Kumano Suigun, a group of skilled maritime warriors who played a role during the Genpei War between the Taira and Minamoto clans.
The Kumano Suigun were known for their exceptional knowledge of the sea. They understood local currents, winds, and coastal waters and were highly skilled in navigation, shipbuilding, and seafaring.
Their maritime traditions are also believed to have influenced later forms of traditional whaling that developed along the Kumano coast. Hunting whales in the open sea required extraordinary physical strength, swimming ability, courage, and teamwork.
Although Kuroshima is now uninhabited, the island’s isolated forests and rocky coastline retain an atmosphere that allows visitors to imagine the maritime history that once unfolded in these waters.
A Mysterious Forest of Subtropical Plants
A Lush Island in the Warm Waters of Kumano
One of the most distinctive features of Kuroshima is its lush vegetation. The warm climate of the southern Kii Peninsula allows subtropical plants to thrive, creating a landscape that can feel surprisingly tropical despite being on Japan’s main island of Honshu.
The dense green forest contrasts beautifully with the deep blue and emerald-colored waters of the Kumano Sea. On sunny days, the sight of the forest-covered island surrounded by clear ocean water is particularly spectacular.
Caves Shaped by the Ocean
Kuroshima is also known for the numerous caves and openings scattered along its rocky coastline.
These caves were gradually carved into the rock by the relentless action of waves over long periods of time. They provide a fascinating example of how the forces of the ocean have shaped the coastline.
In some locations, traces of marine tube worms known as yakko-kanzashi can be found inside the caves, adding scientific and geological interest to the island.
The Remarkable Shape of Taijima
An Island Resembling a Sea Bream
Located close to Kuroshima, Taijima is famous for its unusual silhouette.
When viewed from the mainland, the island looks remarkably similar to a sea bream swimming through the water. This distinctive natural shape is the origin of its name and has made Taijima one of the memorable landmarks along the Kushimoto coast.
The “Eye” Created by Natural Erosion
One of the most fascinating features of Taijima is a hole in the rock that appears to form the island’s eye.
The opening was naturally created by the long-term erosion of the rock by waves. Depending on the time of day and the season, sunlight or moonlight can appear through the opening, producing an especially atmospheric scene.
Because the appearance of the island changes with the weather, light, and position of the sun or moon, Taijima offers a slightly different view each time it is seen.
Kawachi Festival and the Sacred Island
A Traditional Festival on the Sea
Kuroshima has a particularly strong connection with the traditional Kawachi Festival, held in the Koza district of Kushimoto Town.
This historic festival is one of the important traditional celebrations of the Kumano region and has been designated as a National Important Intangible Folk Cultural Property.
During the festival, beautifully decorated boats travel across the water, and religious ceremonies are performed around Kuroshima. The sight of the boats moving across the sea against the backdrop of the forest-covered island creates a uniquely beautiful and spiritual scene.
Kuroshima Shrine
Kuroshima itself is regarded as a sacred place in connection with the festival and local religious traditions.
A small shrine known as Kuroshima Shrine is associated with the island. Local people have traditionally prayed here for safe fishing, safe voyages, and abundant catches.
A Forest That Supports the Sea
Kuroshima is also known as a “fish-attracting forest”, or uo-tsuki-rin. The term refers to coastal forests that help support marine ecosystems.
The vegetation on the island helps retain nutrients and contributes to the surrounding marine environment. In this way, the forest and sea form an interconnected ecosystem that supports fish and other marine life.
Geological Heritage of the Nanki-Kumano Geopark
Rocks Shaped over Geological Time
Kuroshima and Taijima are recognized as geological sites within the Nanki-Kumano Geopark.
The islands are primarily formed from conglomerate rock, created when pebbles and other sediments became compressed and cemented together over geological time.
The unusual rock formations and coastal landforms provide valuable evidence of the geological history of the Kii Peninsula. For visitors interested in geology and natural history, the islands offer an opportunity to observe the long-term interaction between the land and the sea.
Part of Japan’s Whaling Heritage
“Living with Whales”
The islands are also associated with the traditional whaling culture of the Kumano region.
Because of this connection, Kuroshima is included among the cultural properties associated with the Japan Heritage story “Living with Whales.”
Traditional whaling was deeply connected with the communities of the Kumano coast. Whales provided food and other resources, while whaling itself became an important part of local history and culture.
The islands therefore provide an opportunity to understand how the people of southern Wakayama developed a close relationship with the sea and its natural resources.
Experience the Islands from the Sea
Kayaking and Canoeing Around Kuroshima
Kuroshima can generally be approached by boat, canoe, or kayak. In recent years, sea kayaking has become a popular way to explore the waters around the islands.
Seeing Kuroshima and Taijima from the water offers a completely different perspective from viewing them from land.
Kayakers can approach the rocky coastline and, where conditions allow, observe the caves and unusual rock formations at close range. The clear water and peaceful surroundings also create a strong sense of being immersed in nature.
A Quiet Coastal Escape
During the warmer months, the surrounding waters become popular for swimming and other marine activities. The area can become particularly lively during Japan’s summer holiday period around Obon.
At the same time, the islands themselves remain uninhabited and remarkably peaceful. Their secluded atmosphere makes them an appealing destination for travelers who want to experience the natural beauty of the Kumano coast away from crowded tourist areas.
A Special Place Where Nature and History Meet
Kuroshima and Taijima are much more than beautiful islands floating offshore.
Their landscapes are connected with the legends of the Kumano Suigun, the traditional whaling culture of the region, local religious beliefs, and the geological history of the Kii Peninsula.
The dense subtropical vegetation of Kuroshima, caves carved by waves, unusual conglomerate rock formations, and distinctive silhouette of Taijima create a landscape found nowhere else.
Looking across the sea toward these mysterious islands, visitors can imagine the sailors and fishermen who once traveled these waters and the communities whose lives were closely connected with the ocean.
For travelers exploring Kushimoto and southern Wakayama, Kuroshima and Taijima offer a fascinating opportunity to discover the natural beauty, maritime history, and spiritual traditions of Kumano.
Take time to admire the islands from the coast, or experience their beauty from the water, and discover the unique world where the sea, nature, history, and legend come together.