Hagi Geopark: Dragon’s Causeway Area
The Dragon’s Causeway, referred to in Japanese as the Ryū-ga-tōtta-michi (literally, the “Path the Dragon Took”) was so named for its geological similarities to the Giant’s Causeway in Northern Ireland. It was created by a huge flow of lava that traveled for more than 14 kilometers through the Tama river valley about 400,000 years ago. The lava flow created many distinct landscapes, including Mt. Irao and the outstanding examples of columnar jointing at Tatamigafuchi and Ryūrinkyō.
Tatamigafuchi is a popular tourist site located about halfway along the ancient lava flow. The Tama river has created a canyon through the distinct rock made by the lava flow. Called columnar jointing, the stones appear to have been fitted together, but they are in fact the result of a natural phenomenon. As the lava flow cooled, its surface shrank, forming cracks in a hexagonal pattern. These cracks allowed air to enter the still-cooling molten rock, causing the cracks to deepen and the rock to cool faster. The cycle of shrinking, cracking, and cooling continued, eventually creating the six-sided columns that can be seen today. The Ryūrinkyō Ravine area, 5 kilometers farther down the Tama River from Tatamigafuchi, also has examples of columnar jointing. Ryūrinkyō’s name was chosen by local schoolchildren.
Access: 20 minutes by taxi from JR Susa station
Tatamigafuchi Google Maps link: here
Ryūrinkyō Google Maps link: here
