Sanzen-in Temple is one of the five monasteries of the Tendai sect of Buddhism, and is said to have originated in 782-806 (Enryaku era) when the great teacher Saicho built a hall called "Enryu-bo" in the south valley of the east pagoda, one of the sixteen valleys of the three pagodas of Mount Hiei, and called it "Enryu-bo". The Oujo Gokuraku-in Temple (Important Cultural Property), where the National Treasure Amida Sansonzon is enshrined, is located, is known for its beautiful garden with cedar groves and mosses. Surrounded by mountains, visitors can enjoy the scenery of the four seasons. During the season of fresh green leaves, the carpet of moss and blue maples in Ariseien are especially beautiful.
The leaves turn red from mid-November to the end of November every year, and the maple trees in the other garden, Shuheki-en, turn vivid colors. The sight of the red and orange leaves falling on the moss and piling up is an exceptional beauty.