The 3rd Tendai abbot Ennin (Jikaku Daishi, 794-864) trained in the northern mountains of Mt. Hiei during the Tencho era (824-834) and built the Shuryogon-in, opening the Yokawa compound. Having brought back many scriptures and ritual implements from his studies in Tang China, he made Yokawa the center of Tendai esoteric Buddhism. Yokawa is the very land of his founding, dotted with halls associated with him such as the Shiki-Kodo and Eshin-do that honor his legacy.

Shinran (1173-1262) climbed Mt. Hiei at age 9 and trained as a Tendai monk for 20 years. Yokawa is considered one of the places where Shinran devoted himself to nenbutsu practice, and it is honored as a training ground that nurtured the spiritual foundation for his later founding of the Jodo Shinshu school.

Dogen (1200-1253) climbed Mt. Hiei at age 13 and was ordained as a Tendai monk. His training on Mt. Hiei including Yokawa formed the intellectual foundation that led to his later founding of the Soto Zen school. As the "mother valley of Japanese Buddhism," Yokawa holds historical significance as a training ground for the founders of Kamakura new Buddhism.