The Nanyo area of Ehime Prefecture is blessed with abundant water. It lies on the west coast of Shikoku Island, looking out on the Uwa Sea and bathed by the warm Kuroshio Current. Along the coast, rainfall levels are typical of most of Japan. But inland, the Onigajo Mountain Range receives substantially more rain, with some 2,700 millimeters observed each year. Much of that water flows quickly down to the sea, molding the topography of the area. The Yakushidani Valley is among the most beautiful in the country. Thanks to its many waterfalls and watercourses, it has become a popular destination for canyoning. Carved out of the steep slopes, the Izumidani rice terraces are known for the quality of the grain that is grown there, which is attributed to the purity of the water flowing down from the mountains. Offshore, the warm water from the Kuroshio Current mixes with the nutrient-rich fresh water from the mountains, making an ideal habitat for coral and a remarkable variety of marine life. On this edition of Journeys in Japan, Michael Keida follows the flow of this water, from the mountains slopes down to the ocean bed.