Gassan Wine Mountain Grape Research Institute is a winery in Asahi Town, Yamagata Prefecture that produces wine mainly using mountain grapes. Its origins date back to the culture of doburoku made by local ascetics and residents from wild mountain grapes, and in 1979, the agricultural cooperative obtained a liquor manufacturing license and Gassan Wine was born. At first, the wild grapes used as the raw material for wine were harvested from the wild, but in pursuit of quality and stable supply, they began cultivating them. Currently, about 70 farmers are working together to produce wild grapes with excellent sugar content and juice content. Among them, hybrid varieties such as ``Yama Sauvignon'' and wines made using traditional Koshu grapes are also highly rated. Gassan wine is characterized by a flavor that makes the most of its unique richness and acidity, and is loved by many wine drinkers. Enjoy the unique flavors of Yamagata with a cup that incorporates local nature and history.