Osu Kannon is a temple of the Chisan branch of Shingon Buddhism, holding the rank of bekkaku honzan, a designation of special standing within its school. Its formal name, Kitanosan Shinpukuji Hoshoin, was granted by Emperor Go-Daigo in 1333. The temple stood originally in what is now Hashima in Gifu prefecture and was moved to its present site in Nagoya in the early seventeenth century, during Tokugawa Ieyasu's development of the city.
The temple is better known locally for the market in the streets around it than for its books, but the books are why it appears in this atlas. The Osu Bunko, the temple's library, holds a large collection of classical Japanese and Chinese texts, several of them designated National Treasures of Japan.
Temple libraries of this kind were working collections and not museums, and the distinction explains their survival. Monks copied, collated and stored texts because the texts were needed for study and for ritual, and a lineage of monks went on doing that for centuries with no expectation that anyone outside the community would ever ask. Nothing was preserved because it was rare. Things became rare because everywhere else stopped preserving them. The atlas records the temple as a custodian as well as a religious site, because those are two different claims: what it believes and practises belongs in one place, and what it happens to hold, and how a scholar can reach it, belongs here.