Spring Water QualityKusatsu Hot Springs: The Very Definition of Quality Stating the facts as they are… spring quality we are proud of.
Due to its naturally flowing strong acidic water, there are many anecdotes that tell the story of one of Japan's prominent spas.
Here is a look at its quality. As evidenced by the common expression "Kusatsu yoi toko, ichido wa o-ide" (Come to Kusatsu once in your life, since it's such a wonderful place.), there are reasons why it is revered as a famous spa.
Strong acidity: the key to its renowned antibacterial powersIn only ten days, a 6-inch nail left in the hot spring is reduced to a mere skeletal shard (as seen in the photo on the right). A 1-yen coin (made of aluminum) would dissolve without any trace in only a week. The secret to Kusatsu Onsen's sterilizing powers is its strong acidity.
Experiments have proven e-coli bacteria cannot survive for even one minute in Kusatsu's spring waters, and virtually all other bacteria and fungi are unable to proliferate and soon die. This is why these waters are reputed to have beneficial, therapeutic affects. A good hot spring is like a good doctor. Kusatsu Onsen is proud of its century long reputation that "it can cure any ailment except heartache."
Main contentsAcidic spring water containing sulfur, aluminum sulfate and chloride
Main therapeutic benefitsRelief of neuralgia, muscular and arthritic pain, skin ailments, stiff shoulders, bruises, sprains, chronic fatigue, chronic women's diseases, diabetes, high blood pressure and hardening of the arteries; promotion of general health and convalescence, etc.
Specially chosen bathtub materialsThe yubatake is the symbol of Kusatsu. Here, hot water from the spring's origin gushes down wooden channels made from five-centimeter thick pinewood still containing large amounts of resin. Fine quality pinewood or Japanese cypress rich in resin is the optimum choice of material to continuously withstand acidic spring water. This is why many inns still have old, wooden bathtubs made of similar materials. Thus, the quality of Kusatsu's spring water also serves to create a typically rustic hot spring atmosphere.
Water Output: A Completely Natural FlowKusatsu Onsen boasts the largest natural output of any hot spring in Japan.
Trails of steam seen rising into the air all over the town enhance any traveler's experience.
Let's take a look at this incredible amount of water that enables the continuous flow of the natural hot spring.
Kusatsu Onsen is rightfully proud of both the quality and quantity of its waters.
Unmatched Quality and QuantityIn Kusatsu, more than 32,000 liters of spring water gush out every minute – the equivalent of some 230,000 barrels per day. The spring's source is Mt. Shirane, an active volcano. This makes it possible for all Japanese style inns, hotels and spa facilities in Kusatsu Onsen to continuously provide their guests with spring water that doesn't need to be reheated, diluted or otherwise adjusted. This lavish amount of water allows visitors to have a luxuriously sensational experience.
Output of Major Hot Spring Sources (from the Kusatsu Tourism Directory)
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