Over 900 years ago a traveler searching in a mountain valley for ingredients from which to make medicine, stumbled across a hot spring source flowing out of the ground. He set up a hot spring spa which later became a mountain ryokan which his ancestors are still running today. This is the hot spring that feeds the onsen at Takahan. It qualifies as a true onsen as the water comes from source without any kind of interference such as reheating, storing, or circulating. The same spring source feeds the onsen at Nakaya and Yama-no-Yu onsen.
Once a year the source of the onsen which is in a cave at the end of a small hand-dug tunnel is given a clean and we were very privileged to have a look.
Hidden in the mountains is a small locked door. Barefoot, wearing the bare minimum of clothing and a head torch we stepped into the darkness of the rock tunnel. It was ankle deep in hot onsen water. The water comes out of the ground at about 45 degrees and once it reaches the onsen bath a couple of hundred meters away it is still around 43 degrees. The water is very highly regarded among onsen enthusiasts for its mineral content and silky texture.
The tunnel is like a steam sauna – incredibly hot and humid. You have to crouch to make your way through, and with rough rock and stones under the water you tread cautiously. Half way along is another mountain spring with water pouring out year round at about 21 degrees.
Heading further underground you come to the point where the hot onsen water is coming out of the mountain. It falls into a small pool and the water has large bits of sulpher floating in it named “yubana” or hot water flowers, due to their appearance.
Apparently the water is rain from about 5 decades ago. It seeps through the ground to the point where it is heated by magma, and then coming to layer of rock which it cannot penetrate, it flows until coming out of the earth at the hot spring. The area of Yuzawa where the spring is found is know as Yumoto, or source of the spring.
Having struggled to take photographs in the steam by the light of the head torches we made our way out along the tunnel back into the lush greenery of the Yuzawa mountains, and were very glad to be out of the sauna like conditions. Scrubbing the hot spring pool in that heat would be some task.
Snow Country is blessed with many great onsen which have been an important part of life in the region. Spare a thought for their long history and founders when you next enjoy a soak in the soothing waters of a true Japanese hot spring bath.