Guida
The 'Oni no Sentaku Itta' (Devil's Washboard) surrounding Aoshima Shrine is one of Miyazaki Prefecture's most iconic scenic spots. As the name suggests, the coastline is covered in a unique pattern of rhythmic rock formations that look exactly like giant traditional Japanese washboards lined up along the shore. This area is a designated National Natural Monument, allowing visitors to witness the breathtaking sculptural beauty crafted by nature over millions of years.
This extraordinary landscape was formed by sedimentary rocks (alternating layers of hard sandstone and soft mudstone) that originated in the ocean during the late Miocene epoch, roughly 7 million years ago. These geological layers, once submerged, were brought to the surface by tectonic shifts. Over countless ages, the relentless power of the waves and seawater eroded the surface, resulting in the distinctive undulating pattern seen today. This geological formation stretches for about 8 km from Aoshima southward toward Kinchaku Island.
The greatest attraction is the mesmerizing view of the regular, rhythmic undulations carved into the coastline by the waves. From a distance, the sight of the waves crashing against these rhythmic ridges creates a surreal, otherworldly atmosphere. When the tide recedes, the landscape transforms into a network of tide pools and exposed rocky areas, offering a fascinating look at the complex topography created by nature's hand.
While the area can be visited year-round, the experience changes dramatically depending on the tides. If you wish to enjoy beachcombing or observing tide pools, it is highly recommended to check the local tide tables in advance to plan your visit during low tide. Additionally, during bright daylight hours, the contrast between the deep blue sea, the white crashing waves, and the unique textures of the dark rock formations is exceptionally vivid, making it a perfect time for photography.
During low tide, the area becomes a natural classroom. You can enjoy beachcombing and exploring the tide pools, where small fish, crabs, and various shells can be found. Searching for these tiny creatures among the rocks is a wonderful way to feel a close connection to the local ecosystem. It is an engaging activity for families and children to observe the natural world up close.
The 'Oni no Sentaku Itta' stretches approximately 8 km south from Aoshima Shrine. Since Aoshima Shrine itself is a very famous spiritual site, a common and highly recommended route is to visit the shrine for a blessing before exploring the natural scenery. The surrounding coastline is also a popular driving route, offering beautiful views of the Miyazaki ocean.
To fully enjoy the natural environment, wear comfortable and practical clothing. Because the terrain includes rocky areas and slippery surfaces, we strongly recommend wearing sturdy, non-slip walking shoes rather than sandals. Please be extremely careful with your footing when exploring tide pools or rocky shores.