Tamagawa Onsen is unique in Japan for two reasons. The first is that it is the source of the largest volume of spring water, with water rising to the surface at a rate of 9,000 litres per minute. With water temperatures of up to 98 degrees at its source, the sight of the hot spring water gushing out of the earth presents an incredible display of the force of nature. The Onsen’s second claim to fame is that the water has the highest acidity of hot spring water in all Japan with a pH of 1.2. This sterilising water is said to be beneficial for a range of ailments. The unique hot spring water also contains small amounts of radioactive radium gas that combines with the scent of sulphur.

Furthermore, what makes the hot spring rather exceptional is that Tamagawa Onsen has one hot spring inn specialising in treatments and recuperation under the supervision of on-site medical staff. Overnight stays including two meals are available at Ryokanbu and accommodation with self-catering facilities is on offer at Jisuibu. Ryokanbu provides an alternating menu of healthy meals so that even long-term guests never get bored!

Natural stone saunas are also available in an outdoor tent a 5-minute walk from the main building. Note that guests should bring their own towels or mats to lie on in the stone saunas, these can be purchased at the shop. Be sure also to wear comfortable clothes and shoes for the walk.

The nearby Tamagawa Onsen Nature Trail is a 30-minute circular trail. The one-kilometre trail includes highlights of “Obuki”, source water gushing out of the ground, “Ganban”, natural hot stone saunas, and the “Funkiko” fumaroles of steam roaring out of crevices in the ground. Come and experience these forces of nature for yourself!