The Suntory Tennensui Oku-Daisen Beech Forest Factory offers free public viewing of the factory where soft water refined deep underground is bottled. A giant diorama and video show visitors how rain turns into mineral water, and they can learn up close about the filling line and environmentally friendly systems. After the tour, visitors can also sample various brands. Reservations are required, making it easy to incorporate into your itinerary and a great way to experience a factory tour for the first time.

A unique highlight of this factory is the "snow room," which utilizes heavy snowfall. A guide will explain the sustainable system that stores snow in winter and reuses it for air conditioning and equipment cooling in summer. The grounds, surrounded by beech forests, are perfect for photos, and visitors can experience the relationship between water and the forest with all five senses, both inside and outside the factory. Tours, suitable for groups of 2-40, last approximately 60 minutes.

Oku-Daisen was selected as Japan's third water source, following the Southern Alps and Aso. The area is dotted with refreshing spots such as the Kitanizawa Gorge and Kagamiga-nari Plateau, and you can enjoy a "water hometown drive" in addition to sightseeing.