A Brief Explanation: What is the "Oyama-do"?

The Oyama-do was a road actively used by commoners for Oyama pilgrimages*. It ran from Akasaka-mitsuke, through Aoyama, Ikejiri, and Sangen-jaya, passed through Setagaya Kamimachi, crossed the Tama River at Futako-tamagawa, and continued through Mizonokuchi, Atsugi, and Isehara to reach Oyama.

* Oyama-mairi (Oyama Pilgrimage) was a form of religious practice among commoners that spread during the Edo period, consisting of a journey to worship at the "Oyama Afuri Shrine" located in what is now Isehara City, Kanagawa Prefecture. It became particularly popular among farmers and merchants, and eventually incorporated elements of tourism, becoming a representative form of popular culture in the Edo period.

Beyond Isehara, the road passed through Hadano, crossed a checkpoint at the foot of Yagurazawa, and went over the Hakone Ashigara Pass, which is why it was called the Yagurazawa Okan (Yagurazawa Road)*.

* Yagurazawa Okan was a highway developed during the Edo period that connected Akasaka Gate of Edo Castle to Numazu-juku in Suruga Province via Sagami Province and Ashigara Pass, and also functioned as a secondary road to the Tokaido.

The Yagurazawa Okan was a major road connecting Odawara and Edo in the Middle Ages, and Setagaya, located near the middle, was valued as a key transportation hub.

When the Edo period began, the shogunate focused its efforts on developing the Tokaido and Koshu-kaido, so the Yagurazawa Okan, which lay between them, was relegated to use as a waki-okan (secondary road)*.

* Waki-okan is a general term for major roads other than the Five Routes during the Edo period.

However, from the mid-to-late Edo period, as Oyama-ko (Oyama Confraternities)* were formed among the commoners of Edo, Oyama pilgrimages became explosively popular.

* An Oyama-ko is a group of people from the same trade or region that was popular, mainly in the Kanto region during the Edo period, for the purpose of making Oyama pilgrimages.

Gradually, a shortcut was created that branched off from the Yagurazawa Okan at Sangen-jaya and passed through Shinmachi and Futako, and this became the main route.

At the summit of Mount Oyama stands the Oyama Afuri Shrine, which gathers faith for abundant harvests and prosperous business.Uryuzan Oyama-dera Temple also became a center of Fudo worship, and because it was said that "when clouds cover Oyama, it will rain," it was deeply revered by farmers, and it is said that during droughts, village representatives would climb the mountain many times to pray for water.

Reference: "Setagaya Digital Museum" website

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