Maruyama Shrine (丸山神社 (東京都港区))

Maruyama Shrine sits on what was once a literal hill — maruyama means “round mountain” — though the landscape has been so thoroughly leveled by centuries of Tokyo’s expansion that the shrine now occupies a modest rise barely noticeable to the modern eye. Established in 1594 by Ōta Yasusuke, a retainer of Tokugawa Ieyasu, the shrine was positioned to protect the western approach to Edo Castle. What survives is not grandeur but specificity: this is one of the few shrines in central Tokyo where the original Edo-period boundary stones remain embedded in the pavement, marking a sacred precinct that has held its ground through four centuries of radical urban transformation.

Maruyama Shrine was founded in 1594, during the early years of Tokugawa rule, when Edo was being transformed from a provincial outpost into the shogunal capital. Ōta Yasusuke, a direct vassal of Tokugawa Ieyasu, established the shrine as a guardian deity for his residence and the surrounding district. The location was strategic: the hill overlooked what would become Azabu, a district housing many samurai estates. The shrine originally enshrined the spirit of the land itself — the yama-no-kami, or mountain deity — reflecting the ancient practice of venerating prominent landscape features. During the Meiji period, the shrine was formally registered and its kami redefined within the state Shinto framework, but local residents continued to worship the hill’s protective spirit much as their ancestors had.

Oyamakui no Kami is the principal deity, a mountain god associated with land protection and boundaries. This kami appears in both the Kojiki and Nihon Shoki as a child of Izanagi and Izanami, representing the sacred nature of mountains and elevated places. In the Edo period, Oyamakui was particularly venerated by landholders and those establishing new territories, making the choice fitting for a shrine founded by a Tokugawa retainer securing new land. The shrine also venerates Uganomitama no Kami, the Inari deity of grain and prosperity, added during the Edo period when merchant activity increased in Azabu. The dual enshrinement reflects the district’s evolution from samurai estates to commercial neighborhood.

The hill itself was believed to house a tsuchigumo — an earth spider, a term used in ancient texts for both supernatural creatures and indigenous peoples who resisted imperial rule. According to local tradition, when Ōta Yasusuke first surveyed the site, workers discovered a large hollow stone at the summit containing what appeared to be ancient ritual implements. Rather than disturb the site, Ōta ordered the shrine built directly over it, incorporating the older sacred presence into the new Tokugawa order. Residents in the Edo period reported that digging near the shrine’s foundation invariably yielded fragments of Jōmon-period pottery, suggesting the hill had been a ritual site for thousands of years before the shrine’s formal establishment.

The current main hall was rebuilt in 1964 after wartime destruction, but it preserves the compact scale of the original Edo structure. The shrine’s most significant features are its boundary markers — five stone pillars dating to the early 1600s that demarcate the sacred precinct. These stones bear inscriptions in archaic script and remain exactly where they were placed, now surrounded by modern apartment buildings and convenience stores. The shrine grounds include a small grove of kusunoki camphor trees, one of which predates the shrine’s founding and measures over five meters in circumference. A stone-lined spring once flowed at the base of the hill but was capped during postwar development; a commemorative stone marks its location.

• Maruyama Taisai (September 15) — The annual festival featuring a mikoshi procession that follows the Edo-period route through Azabu’s narrow streets, maintaining the original boundary patrol function
• Hatsumode (January 1-3) — New Year worship draws primarily local residents; the shrine offers clay figurines of the protective tsuchigumo as commemorative amulets
• Yama-biraki (June 1) — A mountain-opening ritual that acknowledges the shrine’s origin as a sacred hill, with prayers for safety and protection of the district

Late afternoon on weekdays, when the office workers have left and the evening light angles through the camphor grove. The shrine is most itself in these quiet hours, when the absurdity of its survival becomes clear: a sixteenth-century hill shrine completely surrounded by glass towers, still receiving offerings of rice and sake. September brings the main festival and a rare chance to see the streets temporarily reclaim their pre-modern configuration.