Guide
Yakatayishi no Nanatsukama is a series of sea caves located on the coast of Karatsu City, Saga Prefecture, characterized by well-developed basaltic columnar joints. As a designated National Natural Monument within the Genkai Quasi-National Park, it is a highly significant scenic spot. The area features several caves along the steep, 40-meter-high cliffs, which are collectively known as "Nanatsukama" (Seven Caves). Including those hidden below the water line, the actual number of caves exceeds seven. The central cave is particularly impressive, reaching depths of up to 110 meters, showcasing the dynamic power of natural erosion. On clear days, the observation deck offers an expansive view that stretches as far as the islands of Iki and Tsushima.
The geology of this area was formed by alkaline basalt eruptions approximately 3 million years ago. The columnar joints, created during the cooling process of the lava, form a pattern of regular, vertical pillars that create a truly awe-inspiring landscape. The area also holds local legends; the name "Dokarisaki" is said to be linked to traditions involving Empress Jingū's expeditions, where sake cups (doki) were offered to the sea gods to pray for victory or safe returns. Nearby, the Dokarisaki Shrine is dedicated to the goddess Kichinashihime, preserving the cultural heritage of this coastline.
The highlight is the sight of the sea caves carved into the cliffs. The central cave is exceptionally long and deep, demonstrating the grand scale of natural erosion. Another notable feature is "Megane Iwa" (Spectacle Rock) near the western edge, named for its resemblance to a pair of glasses when reflected in the sea. The dark basalt cliffs rising directly from the ocean create a striking color contrast with the blue sea and white sea spray. From a boat, you can enter the mouth of the caves to experience the scale of the geological formations up close—a perspective impossible to fully appreciate from land.
As an outdoor natural site, there are no fixed opening hours, but your experience will depend heavily on weather and sea conditions. On sunny days, visibility from the observation deck is excellent, allowing for long-distance views. If you plan to explore via boat, please note that excursions are subject to wave height and tides. It is highly recommended to check the local vessel operation status before visiting, as high waves or swells may prevent boats from entering the caves. While beautiful year-round, the best time for a boat tour is during calm seas and high tide.
There are two primary ways to enjoy this site. First, you can walk the observation decks and trails to look down upon the cliffs from above. Second, you can take a sightseeing boat, such as the "Ika-maru," departing from nearby ports like Imari or Yobuko. Taking a boat allows you to witness the sheer scale of the sea caves from the water level, an experience that is truly immersive. The area is also known among advanced divers for its rich underwater environment and natural basalt structures.
The area is maintained as the Nanatsukama Garden, which includes parking lots and restrooms for visitors. Nearby landmarks include "Megane Iwa" and the