residences for the daimyō, his family, and retainers. The oldest structure in the category is a Bunroku-era secondary donjon called the Northwest Small Tower, which is located at Matsumoto Castle. Modern and historical residences Residential architecture includes two categories: from the Meiji period onward and , which date to before 1867. Presently, the only modern residential National Treasure is the Akasaka Palace in Tokyo, which was built in 1909. Fourteen National Treasures, dating from between 1485 and 1657, are listed in the historical residences category. Ten are located in Kyoto. The structures include teahouses, shoin, and guest or reception halls. Structures related to industry, transportation and public works In 2014, the former Tomioka Silk Mill, Japan's oldest modern model silk reeling factory was designated as the only National Treasure in the category of . Established in 1872 by the government, this is—after the Akasaka Palace—the second modern (post-Meiji) structural National Treasure. The designated property includes several buildings such as the silk reeling mill and the East and West cocoon warehouses. Schools One of Japan's oldest schools, the Kaichi School in Matsumoto, Nagano Prefecture was designated in 2019 as the only National Treasure in the category of . The institution was established shortly after the Meiji Restoration and relocated to the extant western-style building in 1876. Shrines National Treasures in the category of include main halls (honden), oratories (haiden), gates, offering halls (heiden), purification halls (haraedono), and other structures associated with Shinto shrines. Presently there are 42 National Treasures in this category, dating from the 12th century (late Heian period) to the 19th century (late Edo period). According to the tradition of {{nihongo|Shikinen sengū-sai|式年遷宮祭}}, the buildings or shrines were faithfully rebuilt at regular intervals, adhering to the original design. In this manner, ancient styles have been replicated through the centuries to the present day. The oldest designated extant shrine structure is the main hall at Ujigami Shrine, which dates from the 12th century (late Heian period). About half of the designated structures are located in three prefectures: Kyoto, Nara, and Shiga, all of which are in the Kansai region of Japan. Nikkō Tōshō-gū has five National Treasures. Temples Structures associated with Buddhist temples such as main halls (butsuden, hon-dō and kon-dō), pagodas, belfries, corridors, and other halls or structures are designated in the category . Presently 158 National Treasures have been designated in this category, including two of the oldest wooden