Also called Sōen-in 倉垣院. A treasure storehouse *hōko 宝庫 with a raised floor at Tōdaiji 東大寺. The structure is the best known of its type and was built in the Heian period. It has three sections lined-up on a north-south axis. The entire structure is 9 x 3 bays (ca. 33 m long x ca. 9 m deep). The north and south sections are constructed of logs, azekura-zukuri 校倉造 (see *azekura 校倉). Some scholars believe these two sections were originally freestanding and that the middle part was enclosed at a later date resulting in what is called the *narabigura 双倉 (lined-up storehouses). The center part is enclosed with thick, horizontal planks. The three sections vary in width, with the center enclosure being the broadest. Doors are centered on the front facade of each section. The entire structure is supported by 40 heavy posts, 2.4 m high from their base stones to the floor joists. Posts supporting the roof structure are positioned inside the structure and against the smooth surfaces of the interior walls made by the triangular-cut logs. In the center of each storage area are four posts set in line with those against the walls. The entire structure is covered by a tiled hipped roof *yosemune-zukuri 寄棟造. Until the Taishō period, the roof structure employed the strut-end-triple-beam system, when it was replaced by a western-style truss. The Shōsōin contains treasures collected by Emperor Shōmu 聖武 (701-56, r. 724-49). These were donated to Tōdaiji and dedicated to the Buddha by Shōmu's widow, Empress Kōmyō 光明 in 756.