Aburisan Oyamadera Temple is a temple of the Daikakuji branch of Shingon Buddhism, located in Oyama, Isehara City, Kanagawa Prefecture. It is widely known as Oyama Fudo. Its mountain name is Aburisan, meaning “Mountain of Falling Rain,” and its principal image is Fudo Myoo, the Immovable Wisdom King. The temple is traditionally said to have been founded by Roben, a Buddhist priest of the Nara period.
Oyamadera is sometimes counted among the Three Great Fudo Temples of the Kanto region, together with Takahata-san Kongoji Temple and Naritasan Shinshoji Temple. During the Edo period, it flourished as a popular destination near Edo (present-day Tokyo). It was also widely known through the rakugo comic storytelling performance “Oyama-mairi,” which tells the story of a pilgrimage to Mount Oyama.
Because of its long history and deep religious significance, the temple continues to attract worshippers today.
Mount Oyama, which rises to 1,252 meters at the eastern edge of the Tanzawa Mountains, has been an object of mountain worship since ancient times. Although the precise origins of this religious tradition are unclear, pottery fragments from the Late Jomon period, as well as Sue ware and Haji ware pottery from the Kofun period, have been excavated near the summit. These discoveries suggest that religious activities on the mountain date back to a very early period.
The origin of the name “Oyama” is not certain. One explanation is connected with the enshrinement of Oyama-tsumi-no-Kami, a mountain deity, at the summit after the Meiji period. This deity had previously been worshipped under the name Sekison Gongen.
The Engishiki, a compilation of regulations and records from the early 10th century, lists Afuri Shrine as one of the 13 shrines of Sagami Province. This has led to the theory that Afuri Shrine was founded in the first half of the 8th century. From the Kofun period onward, worship of Mount Oyama gradually developed into a religious tradition that extended across a wide area.
In ancient times, Oyamadera was established with Fudo Myoo as its principal image. Two forms of worship gradually became integrated: devotion to Sekison Gongen, identified with Kannon, the Bodhisattva of Compassion, and worship of the sacred rock formation at the summit; and the belief that Mount Oyama as a whole was a sacred place of Fudo Myoo.
According to the Oyamadera Engi, a history of the temple included in the collection Zoku Gunsho Ruiju, Oyamadera was founded in 755, during the Tenpyo Shoho era, by Roben, the first chief administrator of Todaiji Temple. The principal image was a wooden statue of Fudo Myoo carved by Roben himself.
Temple tradition also identifies Kukai, known as Kobo Daishi, as the third head priest. The temple is said to have been destroyed by a fire following an earthquake in 878, during the Gangyo era, and restored in 884 by Annen.
During the Kamakura period, the Kasuya family became retainers of Minamoto no Yoritomo, and Oyamadera received the protection of the Kamakura shogunate. The temple later went into decline for a time, but it was revived during the Bun’ei era (1264–1275) by Gankobo Kenshizho, who had helped restore Toji Temple in Kyoto.
To master a secret Buddhist ritual intended to bring about the defeat of the Mongols, Kenshizho undertook 100 days of severe ascetic practice on Mount Oyama. During this period, he created two iron statues of Fudo Myoo. One of these statues was dedicated to Oyamadera and is now recognized as an Important Cultural Property of Japan.
At the beginning of the Edo period, Tokugawa Ieyasu introduced reforms at Oyamadera and unified the temple under the Shingon school of Buddhism. The third shogun, Tokugawa Iemitsu, donated funds for the restoration of the temple buildings. Kasuga no Tsubone also visited the temple as Iemitsu’s representative.
From the latter half of the 18th century onward, the pilgrimage to Mount Oyama, known as Oyama-mairi, became increasingly popular. Groups called Oyama-ko were organized in communities throughout the Kanto region, and roads leading to the mountain, known as Oyama-michi, were developed.
During this period, Oyamadera attracted many people who prayed for practical benefits in this life. The town at the foot of the temple prospered as a place serving pilgrims and visitors.
In the early Meiji period, the policies of abolishing Buddhism and separating Shinto and Buddhism led to attempts to eliminate Buddhist institutions on Mount Oyama and transform the mountain into a Shinto center.
In 1876, reconstruction of the Fudo Hall began at the temple’s present location. In 1885, the temple was revived under the name Myooin. In 1915, it merged with Kannonji Temple, and its former name, Oyamadera, was restored.
One of Oyamadera’s most important cultural properties is the pair of iron statues depicting Fudo Myoo and his two attendant boy deities, created during the Kamakura period. They are regarded as outstanding examples of Japanese Buddhist sculpture made from iron.
The statues are displayed to the public on the 8th, 18th, and 28th of each month.
Oyamadera is located at 724 Oyama, Isehara City, Kanagawa Prefecture.
By public transportation: From the north exit of Isehara Station on the Odakyu Odawara Line, take a Kanagawa Chuo Kotsu Nishi bus to the final stop, Oyama Cable. From there, take the Oyama Cable Car and get off at Oyama-dera Station.
By car: From the Atsugi Interchange on the Tomei Expressway, follow National Route 246 toward the Oyama area of Isehara. Municipal parking is available.