Baio-in Temple Main Hall

Baiou-in Main Hall: A Quiet Sōtō Zen Temple in the Sanada Castle Town

Tucked away in the northeastern corner of the Matsushiro castle town, the Main Hall of Baiou-in (Baiou-in Hondō) offers visitors a quiet, contemplative escape from the busier sightseeing spots clustered around Matsushiro Castle. Although modest in scale, this Sōtō Zen temple holds a deeply personal connection to the Sanada family, who governed the Matsushiro Domain for ten generations across approximately 250 years. The Main Hall, together with its imposing temple gate, was registered as a National Registered Tangible Cultural Property in 2014, recognised for its quiet but authentic expression of late-Edo-period Sōtō Zen temple architecture.

For travellers exploring Matsushiro's preserved samurai streetscape, Baiou-in offers something different from the formal residences and public institutions on the standard tour route. Here, the atmosphere is intimate, the visitors are few, and the building itself speaks softly of devotion, family memory, and the resilience of a community that rebuilt its temples after one of the most devastating earthquakes of nineteenth-century Japan.

Historical Background

Baiou-in was founded in 1672 (Kanbun 12) at the request of the Sanada family, the ruling clan of the Matsushiro Domain. The temple was established to pray for the repose of Lady Ukyō, a concubine of Sanada Nobuyuki — the first lord of the Matsushiro Domain — and for her parents. Lady Ukyō was the daughter of Tamagawa Iyo-no-kami Hidemasa, who served as castle warden of Matsushiro, although alternative accounts trace her origins to a pharmacist's family in Kyoto. After Sanada Nobuyuki's death she took Buddhist vows, retired to a nunnery in Kyoto, and was later remembered by the posthumous name Baiou-in-den Shōgaku Myōtei Daishi — from which the temple takes its name.

The temple was opened by the priest Daijō (also recorded as Rinshitsu Daijō), the sixth abbot of nearby Chōkoku-ji, the Sanada family's principal temple in Matsushiro. As a Sōtō Zen temple, Baiou-in is registered as a branch of both Eihei-ji in Fukui and Sōji-ji in Yokohama, the two head temples of the Sōtō school in Japan.

The 1847 Zenkōji Earthquake and the 1861 Reconstruction

The current Main Hall is not the original building. Local tradition records that the temple was severely damaged by the great Zenkōji Earthquake of 1847 (Kōka 4), which devastated the Nagano basin and left thousands dead across the region. The Main Hall was eventually rebuilt in 1861 (Bunkyū 1), in the closing years of the Edo period. The new structure was raised in a deliberately restrained style, prioritising the quiet dignity expected of a Sōtō Zen temple over decorative display.

Why It Was Designated a Cultural Property

On 25 April 2014, both the Main Hall and the temple gate of Baiou-in were registered as National Registered Tangible Cultural Properties under Japan's Agency for Cultural Affairs. This designation recognises buildings of significant historical or cultural value that warrant preservation, while still allowing for active use by their owners.

The Main Hall earned its designation as a faithful and well-preserved example of a regional late-Edo Sōtō Zen temple hall. It is a single-storey wooden building with a hipped roof now clad in metal sheeting, oriented southward within the temple precinct. Its plan follows the classic six-room hōjō (abbot's hall) layout — a configuration developed for Zen temples that arranges six tatami rooms around a central worship space. A notable feature is the front earthen-floor area (mae-doma), which has since been overlaid with timber flooring. With minimal carved ornamentation either inside or out, the building's quiet exterior eloquently conveys the typical character of Sōtō Zen main halls in the Matsushiro region during the early modern period.

The accompanying temple gate, built in the late Edo period, is a yakuimon-style wooden gate roofed with pantiles. It measures 2.7 metres in width and includes flanking walls and a small side door. Despite its compact size, the gate has a sense of weight and presence in its design — its doors fitted with traditional metal fittings called hassō-kanagu and chichi-kanagu — making it a fitting frontispiece for the temple compound.

Highlights and Points of Interest

The Restrained Beauty of Sōtō Zen Architecture

Visitors familiar with the lavishly decorated halls of larger temples will find Baiou-in's Main Hall a refreshing counterpoint. There are no dragons writhing along the eaves, no elaborate transom carvings, no gilded brackets. Instead, the building relies on proportion, the warmth of weathered wood, and the geometry of the hipped roof to create its presence. This austerity is not a sign of poverty but a deliberate aesthetic — Sōtō Zen has long valued simplicity as a path to spiritual clarity.

The Gyoran Kannon: A Bodhisattva Riding a Carp

One of the temple's most distinctive treasures is a statue of Gyoran Kannon — Kannon, the bodhisattva of compassion, depicted standing atop a carp. The image is said to date from the mid-Edo period and reflects the Matsushiro Domain's historic encouragement of carp aquaculture. In recent times, this unusual statue has come to be venerated by chefs, sushi masters, and others whose livelihoods involve preparing food, who visit Baiou-in to pray for skill and good fortune in their craft.

The "Mite Gozaru" Song Monument

In the temple grounds stands a stone monument inscribed with the lyrics of "Mite Gozaru" ("They Are Watching"), a beloved Japanese children's song. The lyrics were written by Yamagami Takeo, a native of Matsushiro, with music composed by Kainuma Minoru. The monument was erected in 1991, and adds a gently nostalgic note to the temple precinct — connecting the historic site to the cultural memory of generations of Japanese children.

The Temple Gate

Even before stepping inside the precinct, visitors are greeted by the southern temple gate. With its tiled roof, balanced proportions, and metal-studded doors, it offers an excellent first impression of Edo-period gateway construction. Take a moment to admire the joinery and the way the side walls and small wicket door are integrated into the structure.

Visiting Information and Access

Baiou-in is located in the northeastern part of the Matsushiro castle town, set within a quiet residential neighbourhood. Because the temple is an active place of worship rather than a museum, visitors are asked to be considerate of religious activities. The exterior of the Main Hall and the temple gate may be appreciated freely from the precinct grounds; access to the interior is generally not available without prior arrangement.

From central Nagano, the Matsushiro area is reached by Alpico Kōtsū bus from stop 3 at Nagano Station Zenkōji-guchi exit, bound for Matsushiro. The journey takes approximately 30 minutes. From the bus terminus at the former Matsushiro Station, Baiou-in is around a 15-minute walk; alternatively, the temple lies about a 10-minute walk from the Sanada-tei Residence, making it an easy detour during castle-town sightseeing. Rental bicycles are available at several locations in the town and provide one of the most pleasant ways to explore Matsushiro's flat, historic streets.

Surrounding Attractions

Baiou-in sits at the northeastern edge of one of Japan's most rewarding small castle towns. After visiting the temple, travellers can easily spend a full day exploring the surrounding area on foot or by bicycle.

• Matsushiro Castle Ruins — The site of the Sanada family's stronghold, originally built by Takeda Shingen in 1558 as Kaizu Castle. A nationally designated historic site, with restored gates and stone walls.
• Sanada Treasure Museum — Houses around 50,000 items donated by the Sanada family, including the Important Cultural Property "Aoe Ōdachi" sword and letters from Toyotomi Hideyoshi, Ishida Mitsunari, Tokugawa Ieyasu, and Takeda Shingen.
• Sanada-tei Residence — A rare example of late-Edo-period daimyō residence architecture, built in 1864 for the mother of the ninth lord. Features a classic seated-view garden.
• Matsushiro Domain Bunbu Gakkō — The domain's school of literary and military arts, opened in 1855. Designated a national historic site, with original drilling halls for swordsmanship, archery, and spear practice.
• Chōkoku-ji — The Sanada family temple, mother house of Baiou-in's opening priest, with the impressive Sanada family mausoleum.
• Matsushiro Onsen — Iron-rich hot springs once said to be a "secret bath of Takeda Shingen," with several inns offering day-use bathing.