Izu, known for its abundant water, has long been a region where sake brewing flourished. While there were dozens of breweries in the mid-Showa era, the number has declined over time, and today only Bandai Brewery remains. Although Bandai was officially established as a company in Showa 10 (1935), sake brewing—specifically doburoku (unrefined sake)—has been practiced in Izu since at least the 1300s, maintaining an unbroken tradition. Bandai carries on this heritage by producing and selling local sake such as "Manyo," "Wakitaya," "Osawazato," and "Hōraku," all of which have deep ties to Izu’s history. Thanks to the efforts of many people involved in sake brewing and technological advances, the brewery environment has undergone tremendous changes over approximately 150 years—from the Meiji, Taisho, Showa, to Heisei eras. These changes extend beyond brewing methods to include taxation, sales and distribution channels, and even agricultural and health concepts. Now, in the Reiwa era, Bandai cherishes the rich natural environment of Izu, inherited from previous generations, and aims to continue brewing sake that reflects the unique character of this historic Izu brewery.