Xiao River, a red-leaf attraction representing the Donghae region. During the Kamakura period, there was a castle of the Asuke clan at Mount Iimori in Korakei, and there were few trees on the mountain. In the early Edo period, it began when Kazunori Sanei of Kokeji Temple planted maple trees and cedars while chanting the sutras to entertain worshipers, and after that, residents who inherited their intentions brought fine maple trees from each district and planted trees. As a result, now about 4000 of the maple trees in the whole mountain are pleasing to the eyes of tourists. Xiao River is blessed with rich vegetation, and it shows different expressions in various seasons, especially in the spring, such as the Katakuri community and the fresh green of maple.