MOUNTAIN SPRING WATER Water for the brewing process in Yoshino-Shuzo comes from a mountain spring.

Our water is supplied from mountain through the horizontal well (cave) which was hand-built by our predecessor. Then it is collected and stored before being used for the brewing process. Many customers think of groundwater when they hear well water, however groundwater in this region is high in iron which makes it unsuitable for brewing process. Mountain spring water is soft.

We believe that our predecessor first dug multiple wells within the property and found it challenging to brew good sake from well water. It is assumed that after many trials, he decided to use spring water from the nearby mountain he owned.


The cave is approximately 150 meters in length. At the end of the cave is a water channel built by ashlars assembled and stacked together.

Our horizontal well is a proof of his great accomplishment in digging the cave by hands with a passion for crafting fine sake.


Because of the soft water used for the brewing process, Koshigoi sake is described as onna-zake (women's sake) with its soft finish.

Katsuura is still surrounded by abundant nature rich in green, and we find many old growth trees in the mountains we own.

Had it not been for the abundant gift from the mountains, Koshigoi could not have been available with its umami, soft finish, and semi-sweet after taste.