Naru Nokobiura
A visible break in the earth’s crust
A split in the earth is clearly visible on this narrow neck on the westernmost peninsula of Naru Island. This is one of the actual faults caused by the pulling forces that moved from the northwest to the southeast and created the Goto Islands.
The site is at the end of the road, where a high wall has been built using the tailings removed during the construction of a modern tunnel. These were piled up to provide protection from the strong winds blowing off the Pacific Ocean—both the typhoons common in late summer and autumn, and cold winter winds. The windbreak provides a lofty view over the ocean and the rest of the island, and directly below it is the unmistakable crack in the earth marking the fault line.
Deposits of obsidian, the volcanic glass that was used for knives, arrowheads, and other important tools dating from Paleolithic times and into the Jomon period (10,000–300 BCE) can be found after about a 20-minute walk in either direction. Knives and other human-made items created from obsidian have been found in the Goto Islands, but despite the large deposits at Naru Nokobiura, none made from Naru Island obsidian have yet been discovered.