Buko Shuzo, established during the Horeki era (1751) in Chichibu, Saitama Prefecture as Yanagida Sohonten, has brewed Bukomasamune using subterranean water from Mount Buko — named one of Japan's Heisei hundred select waters — for over 270 years. The brewery's historic shop and main residence were designated a nationally registered tangible cultural property in 2004, reflecting its deep roots in the Chichibu landscape. Bukomasamune is known for its clean, slightly dry profile that rewards varied serving temperatures, from chilled to warm.