Hashigui-iwa: Wakayama’s Stone Pillars and the Legend of a Bridge Built in a Single Night

Along the coast of Kushimoto in Wakayama Prefecture, a series of towering rock formations known as Hashigui-iwa line the shore, extending nearly 850 meters into the sea. The striking resemblance of these 40 monoliths, both large and small, to the piers of a bridge led to their name, "hashigui-iwa." Created by volcanic activity 15 million years ago, the rocks emerged from underground magma intruding into a long, straight fissure in the softer mudstone, which has since eroded away, leaving the enduring igneous formations.

The natural beauty of Hashigui-iwa has inspired devotion for centuries, as people sensed the sacred presence of such formations and revered them as yorishiro—vessels for the divine. Over time, simple shrines were built: a torii and a miniature shrine on Bentenjima, and an Inari shrine on Motoshima, the closest islet to the shore.

The site is also steeped in local folklore, notably a legend involving the Buddhist sage Kūkai and a mischievous demon. Kūkai purportedly built a bridge to Ōshima island in a single night, but the trickster demon tricked him by imitating a rooster's call, causing Kūkai to abandon the work.

The appearance of Hashigui-iwa varies with the time of day, tide, and weather, making it a breathtaking sight throughout the year. From low tide, visitors can stroll to Bentenjima, the small island nestled within the rock chain. At sunrise, the pillars form a dramatic silhouette against the dawn, while night-time illumination on certain fall evenings adds to the site's mystique.

Hashigui-iwa, situated at the southernmost tip of Honshū, remains an awe-inspiring geosite that continues to captivate visitors with its unique coastal landscape.