Oku Komyoen Onshi Kaikan

Five Registered Structures at Oku Kōmyōen, a Hansen's Disease Sanatorium on Nagashima

Nagashima is a small island off the coast of Setouchi City in Okayama Prefecture, in the eastern reaches of the Seto Inland Sea. For most of the twentieth century it held two national sanatoria for people affected by Hansen's disease, and until 1988 the only way onto the island was by boat. One of those institutions is Oku Kōmyōen. In March 2019 the Agency for Cultural Affairs added five of its structures to the register of Tangible Cultural Properties: the Onshi Kaikan assembly hall, the former Mokake Elementary and Junior High School Third Branch, the Hōanden shrine building, a concrete goods-hauling incline, and the stone Semizo Pier.

These are not monuments in the usual sense. They are the working fabric of a community that people were once compelled by law to enter and forbidden to leave. Read together, the five explain how a settlement functioned when it was cut off from the mainland by water, and they preserve the physical memory of Japan's long policy of segregating those with the disease.

How the Sanatorium Came to Nagashima

The institution did not begin on the island. Its predecessor, Sotojima Hoyoin, opened in 1909 in what is now Nishiyodogawa Ward in Osaka, serving a group of prefectures across western Japan. In September 1934 the Muroto Typhoon destroyed it and killed many residents and staff. The rebuilt facility moved to Nagashima in 1938, taking the name Kōmyōen, and in 1941 it passed to national administration. The larger neighbour on the same island, Nagashima Aiseien, had opened in 1930 as Japan's first national sanatorium of this kind.

The founding dates of the five registered structures track the settlement's growth. The goods-hauling incline went in first, in 1938, followed by the branch school in 1939, the Onshi Kaikan in 1941, the Hōanden in 1943, and the Semizo Pier in 1949. Together they span the years when the community was building itself into a self-contained world on the water's edge.

The Onshi Kaikan

Standing near the centre of the grounds, the Onshi Kaikan was the symbolic heart of the settlement, a hall used for assemblies and communal occasions. Its name carries the sense of an imperial bestowal. The building is timber-framed with a tiled roof and a footprint of about 181 square metres, completed in 1941 and repaired in 2003.

Its front is worth stopping to look at. The wall above the central porch pushes forward and carries a row of three arched windows, and the gable ends of the side lean-to roofs are extended so that the gable reads as a double form. The Agency's own record contains a small inconsistency here: the structured field lists the building as two storeys, while the descriptive commentary calls it single-storey with a half-hipped, gable-entry roof. The published sources have not reconciled the two, so a visitor should treat the exterior itself as the surest guide. The design earned this structure its registration under the criterion for buildings that serve as a model of their type, the only one of the five listed on that ground.

The Branch School

Facing north toward an inlet on the eastern side of the grounds is the former Mokake Elementary and Junior High School Third Branch, known within the settlement as Kōmyō Gakuen. Children living in the sanatorium were taught here, apart from the schools of the mainland. The single-storey wooden building of 1939 has a gabled roof of cement tile and clapboard walls, with a gabled entrance projecting from the centre of the front. Rows of transom-topped glass windows run along the front and back to bring in light, and the roof trusses are braced to the frame with diagonal struts. A repair followed in 2002. Purpose-built schools attached to these institutions rarely survive, which is much of why it was listed.

The Hōanden

On high ground in the northern part of the grounds sits a very small building of reinforced concrete, barely two square metres in floor area, built in 1943 and repaired in 2009. A hōanden was a structure built to enshrine the portrait of the emperor and the Imperial Rescript on Education, objects that schools and public institutions across wartime Japan were expected to venerate. Most were demolished after 1945. This one survives, and its presence at an isolation sanatorium shows how far the state's demand for reverence reached, into a place whose residents had been separated from ordinary society.

The building stands on a plinth with a railing, under a gabled copper roof, and has an iron door at the front. Forked finials and billet logs sit along the ridge in the manner of a shrine, and rounded columns are expressed at the four corners of the exterior. Inside is a single room with a plank floor, boarded walls, and a coffered ceiling. Examples attached to sanatoria are few, which sets this one apart.

The Incline and the Pier

Two civil-engineering works complete the group, and both speak directly to life on an island. The goods-hauling incline of 1938 runs down the western slope above a wharf in the southern part of the grounds. It is a concrete cable-worked trolley line about 45 metres long and 2.7 metres wide, climbing 23 metres from the shore to the facilities on the higher ground, with the track on the north side and a stair on the south. Before any road bridge existed, supplies that reached the island by boat were lifted up this slope.

The Semizo Pier of 1949 lies below the staff quarters on the western side, looking across the strait to the mainland. Built of granite laid in a valley-jointed pattern, it measures about 10 metres long, 2.8 metres wide, and 1.5 metres high, with concrete poured over the top of the stonework. It served as the staff boat landing that linked the island to the mainland. That there was a separate landing for staff is itself part of the history the site records. Everything changed in May 1988, when the Oku-Nagashima Bridge finally joined Nagashima to the mainland. Residents had long sought it, and it became known as the Bridge of Human Restoration.

Why the Five Were Registered

Four of the structures were listed for contributing to the historic landscape of the nation, and the Onshi Kaikan for the quality of its design. Behind the categories lies a larger point. Japan segregated people with Hansen's disease under a succession of laws, from early twentieth-century measures through the Leprosy Prevention Law of 1953, which was not repealed until 1996. In 2001 the Kumamoto District Court found the segregation policy unconstitutional, and the government chose not to appeal. Registering these buildings keeps the material record of that history in place, where it can be seen and understood rather than forgotten.