This pleasant walk along the Shimabara Peninsula’s southernmost shore will bring you up close to the remnants of the region’s oldest volcanic eruptions and show you the many blessings the eruptions have provided to the people who live here.
About 4.3 million years ago, an underwater volcano began to form deep beneath the ocean. This was the birth of what would become the Shimabara Peninsula. Each step in the volcano’s growth produced different material. Once the volcano broke the surface, the lava from early eruptions mixed with seawater to create a large quantity of volcanic ash, which became the fine-grained yellow earth mostly seen here in the south. As the volcano continued to grow, lava flows cooled in the air, forming large reddish-brown basalt rocks. Eventually the island volcanoes would be connected by the massive eruption of a new volcano which became the Unzen volcano cluster; the Shimabara Peninsula was born.