This is the Ryujin-buro (aka Dragon God Bath) located on Kyushu Island near Kagoshima City, Japan. It is a tree and a hot springs and of course, a shrine. It also overlooks the Kinko bay. Many hot springs in Japan are clothing optional, but this particular spring is a shrine. It's best not to insult the God's and wear provided clothing (yukata).
Found these tourists online taking (what looks to be relaxing) dip.