Yagen Onsen Kouzanro (formerly Furuhata Ryokan)

Kouzanro is a day-use hot spring bathhouse standing at the entrance to the Yagen valley in the Ohata district of Mutsu City, Aomori Prefecture, where the Ohata River has carved a gorge through virgin Aomori hiba cypress forest on the Shimokita Peninsula. Yagen Onsen is said to have been opened in 1615 by Jodai Kuranotaro, a warrior who fled north after the Summer Siege of Osaka. The place name Yagen comes from the shape of the spring outlet, which resembled the boat-shaped metal mortar that traditional apothecaries used to grind herbs. The Yagen and Oku-Yagen area was designated a National Health Resort Hot Spring on 23 March 1971. The building once operated as an inn called Furuhata Ryokan, but it suspended business in December 2015; new owners later reopened it under the name Kouzanro, and it now serves day visitors only.

The water is a simple hot spring of the mildly alkaline, hypotonic, high-temperature type. It comes from the Yagen No. 1 source at 47.7 degrees Celsius, with a pH of 7.5 and a total mineral content of 639 mg/kg. Colourless, odourless and tasteless, it nevertheless carries a mineral profile close to that of a sulphate spring and is known for leaving the skin soft and moist long after bathing. Nothing is added or removed: no water, no reheating, no recirculation and no chlorine. The inlet sits at the bottom of the tub, so fresh water rises from below without ever meeting the air and spills continuously over the rim. Even the showers in the washing area run hot spring water.

Bathing consists of a single indoor bath each for men and women, with no open-air bath, sauna or cold plunge. The two-storey wooden building and its bathrooms are built almost entirely of Aomori hiba, and the scent of hinokitiol in the timber rises with the steam. The tubs hold three to four people, and the windows look out onto hiba and beech forest. Admission is 600 yen for adults and 300 yen for elementary school children and younger, with opening hours of 10:00 to 15:00 on weekdays and 10:00 to 17:00 on weekends and holidays. The bathhouse runs for roughly half the year, from late April to the end of October, and closes for the winter from November until mid-April. Parking is available for 20 cars.