Ozawa Sake Brewery, located in Ome, Tokyo, has been documented as far back as 1702 in Genroku-era records, making it one of the oldest continuously operating breweries in the Kanto region. The brewery's Sawanoi brand is its flagship, and Juuku (written as 十右衛門, referencing a historic proprietor's given name) represents a premium small-batch line drawing on the dual spring water sources that distinguish the Sawanoi complex. Tucked into the Okutama valley along the Tama River, the brewery is one of the few sake producers in greater Tokyo that has maintained continuous production through the modern era.




