Genmyo-Ji Temple Sutra Repository

Genmyoji Temple Kyozo: A Prewar Reinforced Concrete Sutra Repository in Iwata

Nestled in the southeastern corner of the grounds of Genmyoji Temple in the historic Mitsuke district of Iwata City, Shizuoka Prefecture, stands a compact yet remarkable structure — the Kyozo, or sutra repository. Built in 1934 during the early Showa period, this reinforced concrete building was designed with a singular purpose: to protect the temple's sacred Buddhist scriptures from fire, a constant threat to wooden temple complexes throughout Japan's history. Registered as a National Tangible Cultural Property in December 2014, the Genmyoji Kyozo stands as an excellent example of prewar concrete construction adapted for traditional religious use, blending Western building technology with the spiritual functions of a Buddhist temple.

Historical Background of Genmyoji Temple

Genmyoji Temple has deep roots in the history of Nichiren Buddhism. The temple was founded in 1385 (Genchu 2) by Nichiju Shonin, the patriarch of the Nichiju school of Nichiren Buddhism. Before becoming a Buddhist monk, Nichiju had studied at Mount Hiei under the name "Genmyo" — a name that would later be given to this very temple. Born into a samurai family in Aizu (present-day Fukushima Prefecture), Nichiju lost both his parents at a young age and entered the priesthood at nineteen. His intellectual brilliance led him to become the head scholar of Mount Hiei at the age of thirty-eight before he descended from the mountain at fifty-eight to spread the teachings of the Lotus Sutra.

During his missionary journeys, Nichiju first established a small hermitage in the Mitsuke area in 1383, which he formally consecrated as Genmyoji Temple two years later. The temple thus holds the distinction of being the first temple personally founded by Nichiju Shonin. Along with Myomanji in Kyoto and Myohoji, Genmyoji became one of the three principal temples of the Nichiju lineage. Its mountain name is Honryuzan.

Throughout the centuries, Genmyoji served as a headquarters of the Kenpon Hokke sect until 1941, when it merged with the broader Nichiren sect under government directive. Today, the temple remains a head temple (Yusho-jiin) within Nichiren Buddhism and continues to be an important center of faith in the Enshu region.

Why the Kyozo Was Designated a Cultural Property

The Genmyoji Kyozo was registered as a National Tangible Cultural Property (Registered Tangible Cultural Property — Buildings) on December 19, 2014, under registration number 22-0441. Its designation recognizes several notable qualities that make it an important example of Japan's early modern architectural heritage.

The building demonstrates the innovative adoption of reinforced concrete construction in prewar Japanese religious architecture. While most traditional sutra repositories were built of wood — often as raised-floor storehouses in the azekura or other log-cabin styles — this kyozo was constructed entirely of reinforced concrete to prioritize fire resistance. The devastating fires that have destroyed countless temple treasures throughout Japanese history made the protection of irreplaceable scriptures a paramount concern, and Genmyoji's choice of modern materials reflects the pragmatic approach of early Showa-era temple administrators.

The structure is further valued for its exterior design, which cleverly mimics the appearance of stone masonry. The outer walls feature artificial stone with an exposed-aggregate wash finish (jinzoseki araidashi), with decorative pilaster forms, cornice moldings, and scored joints creating the illusion of ashlar stonework. This synthesis of modern engineering and traditional aesthetics sets it apart as a fine specimen of its type and era.

Architectural Features and Highlights

The Genmyoji Kyozo is a single-story reinforced concrete building with a gabled roof (kirizuma-zukuri) covered in cement tiles. The building occupies a modest footprint of approximately 13 square meters, reflecting the focused purpose of sutra storage rather than congregational use.

The structure faces west and is positioned in the southeastern corner of the temple precinct. Its principal entrance consists of a doorway on the front (western) facade, fitted with sturdy iron doors — another measure to ensure fire protection. A window on the northern wall is equipped with an eave and can be opened with iron shutters, providing ventilation and light to the interior while maintaining security.

The exterior walls are perhaps the most visually striking feature of the building. The artificial stone finish with exposed aggregate creates a textured, rusticated surface, while the pilaster columns and cornice moldings lend a dignified, almost European character to what is fundamentally a Buddhist storage building. The decorative scored joints complete the illusion of carefully laid stone blocks, giving the compact structure a sense of permanence and weight.

Inside, the kyozo was designed to house sacred sutras and Buddhist texts that have been collected and studied at Genmyoji over its more than six centuries of history. The use of concrete construction, iron doors, and careful attention to ventilation all reflect the paramount importance placed on preserving these invaluable religious manuscripts.

The Omei-ko Festival and Temple Life

While the kyozo itself is a quiet, contemplative structure, the temple that surrounds it is the scene of one of the most cherished annual events in Iwata City. Every year on November 12 and 13, Genmyoji hosts the Omei-ko ceremony, a memorial service for the founder of Nichiren Buddhism. This event also coincides with a festival honoring Kishimojin (Hariti), the Buddhist guardian deity of children and childbirth.

A beloved tradition associated with the festival is the distribution of "kosodate zouri" — small straw sandals believed to ensure children's health and protection from illness. Parents borrow a pair of sandals from the temple for their infant, and the following year they return two pairs as an offering of gratitude. This folk custom, which dates back to the Edo period, transcends sectarian boundaries and draws families from across the region, making it a truly communal celebration of childhood and family well-being.

Visitor Information and Access

Genmyoji Temple is located in the Mitsuke district of Iwata City, along the route of the former Tokaido highway. The temple is easily accessible from JR Iwata Station by taking the Akiba Bus bound for Enshu Morimachi or the Entetsu Bus Route 31 bound for Iwata Municipal Hospital. Alight at the "Kyu-Mitsuke Gakko" bus stop and walk approximately three minutes to reach the temple.

Visitors should note that the kyozo is located within the temple grounds and can be viewed from the exterior. As with all temple visits in Japan, respectful behavior is expected. The temple grounds are open and free to enter, though interior access to the kyozo itself may be restricted. Photography of the exterior is generally permitted.

The area around the temple is rich in historical attractions, making it ideal for a half-day walking tour along the old Tokaido road. Nearby points of interest include the Former Mitsuke School (Kyu-Mitsuke Gakko), a nationally designated historic site and the oldest surviving wooden school building in Japan, dating from 1875; the Iwata Bunko library adjacent to the school; and Awashima Kunitama Shrine, the provincial grand shrine of Totomi Province. The Mitsuke-juku area retains its Edo-period atmosphere in places, with traditional lattice-fronted houses and wooden fences visible along the old highway.

Surrounding Attractions

Iwata City and the wider Enshu region offer visitors a wealth of cultural and natural experiences beyond Genmyoji Temple. The Former Mitsuke School, located just minutes away on foot, is a must-visit destination for history enthusiasts. This five-story Western-style wooden schoolhouse was completed in 1875 and now serves as a museum documenting Meiji-era education, with restored classrooms, period textbooks, and a famous drum said to have been used by Sakai Tadatsugu during the Battle of Mikatagahara in 1573.

Also in the Mitsuke area, the Akamatsu Family Gate and Walls — the residence of Akamatsu Noriyoshi, a Tokugawa retainer who traveled to America aboard the Kanrin Maru — offer another glimpse into Meiji-era heritage. Nearby Yanabiki Shrine (Mitsuke Tenjin) is famous for the Mitsuke Tenjin Hadaka Matsuri, a dynamic festival designated as a National Important Intangible Folk Cultural Property.

For nature lovers, the Kumano-no-Naga-Fuji in the Ikeda district is a nationally designated natural monument — a magnificent old wisteria vine that creates a breathtaking canopy of purple blossoms each spring. Further afield, the Tenryu River and the Tenryu-Hamanako Railway offer scenic excursions through the lush Enshu countryside.