Nishizawa Gorge is one of the most beautiful gorges of the Chichibu-Tama-Kai National Park, which covers over 1250 square kilometers of densely forested mountains, dynamic gorges and crystal clear rivers in the prefectures of Tokyo, Yamanashi, Saitama and Nagano. A very popular spot for Autumn “koyo” red-leaf sightseeing (late October – early November in this area), and best to avoid weekend crowds during this period.