Miniature Japanese shrines
 and , also called (collectively known as ) are small or miniature shrines entrusted to the care of a larger shrine, generally due to some deep connection with the enshrined "kami".
The two terms used to have legally different meanings, but are today synonyms. "Setsumatsusha" can lie either or the main shrine's premises. "Setsumatsusha" are usually 1x1 "ken" in size. They can however be as small as beehives or relatively large and have 1x2, 1x3 or even, in one case, 1x7 bays.
History.
The practice of building "sessha" and "massha" shrines within a "jinja" predates written history. The earliest "setsumatsusha" usually had some strong connection to the history of the area or the family of the enshrined "kami".
During the Heian period, Ise Shrine used to make a distinction between the two types based on whether a shrine belonged to the Engishiki "Jinmyōchō" list ("sessha") or to the "Enryaku gishikichō" list ("massha").
From the Japanese Middle Ages onwards, at other shrines popular "kami" like Hachiman, Inari or were often enshrined in "setsumatsusha", but no clear distinction between the two terms was made. From the Meiji period to the Second World War, a shrine dedicated to family members of a "kami", to the , or the "kami" of the region where the main shrine was, were to be considered "sessha" with a higher rank than the rest, which were called "massha". When the shrine ranking system was abolished in 1946, legally the distinction disappeared, but both terms remained in use out of habit.
Betsugu are another kind of auxiliary shrine their relationships to the main shrine are similar to that of Massha and Sessha. The term is most notable for the extensive betsugu at Ise Grand Shrine.
Architectural style.
Being true shrines, "setsumatsusha" have most features other types of shrines have, including doors and often stairs. However, the is a style normally used only in "sessha" and "massha". It owes its name to the fact that, unlike other shrine styles, it doesn't feature a stairway at its entrance, and the veranda is completely flat. Miniature stairways can however be present. They can be either , that is have the entrance under the gable, or, more frequently, , that is, have the entrance on the side parallel to the roof's ridge (see examples in the gallery). Apart from the lack of a staircase, such shrines belong to the "nagare-zukuri" or "kasuga-zukuri" styles.