Saimyoji, one of the Koto Sanzan temples, flourished as a mountain monastery since its Heian-period founding and received the devotion of Minamoto no Yoritomo and other warriors during the Kamakura period, sustaining its influence. The main hall and three-story pagoda—both National Treasures—were built in that era, preserving the architectural excellence of the age when Yoritomo's faith helped support the temple.