Sugawara no Michizane
A steep slope, , runs from eastern "Honmaru" toward "Hirakawa-mon" in front of the today's Archives and Mausolea Department building. It is said that Ōta Dōkan planted several hundred plum trees in 1478 in dedication to Sugawara no Michizane. Dōkan is said to have built the Sanno-Gongendō here, where two shrines were when the Tokugawa clan occupied the site. With the erection of the "Honmaru" of Edo Castle, the shrine dedicated to Sugawara no Michizane was moved to Kojimachi Hirakawa-chō and later became known as Hirakawa Shrine. Sanno Shrine was first moved to "Momijiyama" of Edo Castle and became its tutelary shrine but was moved again. Today it is known as Hie Shrine.