Seppikosan is produced by Tsubosaka Brewery, founded in 1805 in Himeji City, Hyogo Prefecture, named after Mount Seppiko, which rises behind the brewery and provides the deep-mountain subsoil water used in brewing. Rather than mechanical temperature control, the brewery regulates fermentation through the natural temperature swings of day and night by opening and closing its doors, a technique that shapes the sake's distinctive floral and fruity character. The Seppikosan brand has earned multiple international awards, including Gold at Kura Master 2017 and 2019, and the Junmai Sake Award 2018 Gold Prize.
