For an unique natural experience, make your way to the bubbling pools of Sekibira Onsen. This spot is famous for its mineral-rich waters.
You'll soon see why this Kirishima naturally heated water source is popular with travelers. If you're searching for more to see and do here, Kirishima Shrine, Myoken Hot Springs, and Takachiho Farm are in the area as well. They won't take you very long to reach from Sekibira Onsen.