The city of Yonezawa is known for the quality of its rice and the water which flows down from nearby mountains. Winter is the season when its high-quality sake is brewed in the traditional long-term, low-temperature fermentation process. In the Edo period (1600-1867), rice was very valuable, and so sake would be prohibited whenever there was a rice crop failure. Toko was the one of the few sake breweries which was permitted to continue brewing sake even in these times of famine.