Jogyo Zanmai-do Hall (常行三昧堂)
Jogyo zanmai-do hall is a type of Buddhist hall built to perform the jogyo zanmai which is one of the Shishuzanmai (the four kinds of samadhi) of the Tendai sect. It is also called Jogyo-do hall. Although the Amida Nyorai (Amitabha Tathagata) is placed as the honzon (principal object of worship at a temple), this hall is not an Amida-do hall for the Amida worship, but an hall for the purpose of exercise of the Jogyo zanmai-gyo. Therefore this type of hall was often built in the Tendai sect temple having ascetic exercise halls such as the Enryaku-ji Temple on Mt. Hiei.
It is thought that the first Jogyo zanmai-do hall in Japan was built by Ennin in 851 at the Mt. Hiei.
In the Jogyo zanmai-do hall, the Jogyo zanmai exercise is performed which involves walking around the Amida Nyorai for 90 days while praying to Amida Buddha and revering the Amida Nyorai in mind. For that reason, most of the halls are square shaped, the Amida Nyorai is placed at the center of the hall and the roof is hogyo-zukuri style (all the roof ridges gathering at the center). It may built along with a hokke-do hall which is a type of Buddhist hall built to perform the Hokke-zanmai (Dharma-Lotus Samadhi) exercise which is an important exercise of the Tendai sect along with the Jogyo zanmai. These halls connected together with a corridor are often called "Ninai-do hall."