Karasawa Castle located in Mt. Karasawa with an altitude of 240 m in Sano City, Tochigi Pref. is a large-scale mountain castle, which is counted as one of 7 Fine Castles in the Kanto region. It was built in 927 by Fujiwara no Hidesato, who had just put down the rebellion of Taira no Masakado. The five successive generations of Fujiwara clan resided in this castle, but after that the castle was abandoned. In the later period, the Sano clan (the descendants of Hidesato) restored the castle and used it as the base for the battles fought between the Hojo and Uesugi clans. The Sano clan managed to protect its family property using its diplomatic tact, and was given an important position by Toyotomi Hideyoshi during the Azuchi Momoyama period (1568-1598). When Sano Nobuyoshi, who was brought into the family from the Toyotomi clan, was transferred to Kasugaoka under the order of Tokugawa Ieyasu, Karasawa Castle disappeared from the recorded history. At the ruin of Honmaru (the main castle) stands Karasawayama Shrine, which enshrines Hidesato, the founder of the castle. At the present time remain the stone walls, the masugata-mon (the square gate), and the earthworks, which faintly remind us of the fine castle of the time.