Jinata Onsen (Shikinejima-island)
Shikinejima in Niijima-mura(Tokyo) is a wild hot spring paradise. “Jinata Onsen” is a free mixed bathing open-air bath. You can wear a bathing suit, and it is a rare underwater hot spring in Japan that sinks in the sea at high tide. Since this is a hot spring that springs naturally, the amount of hot water, the weather, and the ebb and flow of the tide will change the amount of hot water.
There are several other free mixed bathing underwater hot springs on the island, so why not stay at an inn within walking distance and visit.
