c) History of preservation/conservation

i) The process of introducing preservation measures The villages in the Shirakawa-go / Gokayama area, composed mostly of Gassho-style houses, had been developing slowly but steadily with increases in the number of households corresponding to increased production of ensho and silk, from the mid-18th to the mid-20th century, until just before World War II. But due to the dramatic advances in the economic condition in Japan in the 25-year period from around 1950 to 1975, the lifestyle in the mountain regions underwent drastic change -- and the whole area experienced radical de-population as more and more people left the rural areas and moved to urban centers. As part of these changes, there are many cases where traditional Gassho-style houses and traditional accessory buildings were torn down or reconstructed into more modern form using contemporary materials and construction methods -- with the result that this region's cultural landscape, which had been formed and maintained over a very long period of time, has virtually disappeared. To compare today's situation with that of a century ago, at the end of the 19th century there were over 1800 Gassho-style houses in 93 villages in the Shirakawa-go / Gokayama area, whereas by 1994 the number of such villages has been reduced to 25; thus all Gassho-style buildings in 60 of the original villages have disappeared, and among this number 17 villages have been abandoned entirely -- with the result that only 144 Gassho-style houses remain in existence today (Appendix 14, photographs). It is a shocking fact that in one century 92% of all Gassho-style houses have disappeared, mostly within a single quarter-century period. During this time of drastic change, many Gassho-style houses in the Shirakawa-go / Gokayama area were relocated and preserved in outdoor museums in various parts of Japan or relocated and reused as restaurants in urban areas. The high level of adaptive reuse suggests that these Gassho-style houses are recognized as very unique examples of Japan's wooden architectural heritage and are valued highly by the Japanese people. The Agency for Cultural Affairs (at that time entitled the National Commission for Protection of Cultural Properties), took serious note of this situation and initiated scientific research efforts on these Shirakawa-go / Gokayama farmhouses in 1951 and again in 1956, and as a result of this research the national government designated as Important Cultural Properties two houses in Shirakawa-Mura (in 1956 and 1971), two houses in Taira-Mura, and one house in Kamitaira-Mura (all in 1958) -- to preserve them on in their existing sites as representative examples of Gassho-style houses. The concept of preserving entire villages was first introduced in Ainokura and Suganuma Villages. In 1970, before the establishment of the system of Preservation Districts for Groups of Historic Buildings in accordance with revisions to the Law for the Protection of Cultural Properties, the village of Ainokura in Taira-Mura and the village of Suganuma in Kamitaira-Mura -- both of which were judged to have a better state of preservation than the other villages in Gokayama -- were designated by the national government (following formal application by each village) as national Historic Sites together with the surrounding forest areas. Any demolition, relocation or non-historic remodeling of Gassho-style houses in these villages is prohibited -- restrictions accepted by all residents. As a result, the Gassho-style houses in both villages remain basically unchanged, with no decrease in number and no compromise in historic value. In Ogimachi, however, the preservation of the village was begun by the local people themselves. In Ogimachi Village in Shirakawa-Mura, where the state of preservation of the Gassho-style houses was also considered relatively good, the people clearly recognized the necessity of preserving the village and in 1971 organized the Association for the Protection of the Historic Village Landscape in Shirakawa-go Ogimachi Village. With the establishment of the Village Residents' Charter in the same year, a preservation movement was initiated to preserve the whole village -- not only the houses but also the fields, canals, roads and forests -- which in combination with the buildings form historic natural features of high cultural value. In 1975 the Law for Protection of Cultural Properties was revised to widen the range of categories and systems of protection, to include new categories such as Intangible Folk-Cultural Properties and Traditional Conservation Techniques for conservation of cultural properties. It was at this time that the category of Preservation Districts for Groups of Historic Buildings was introduced -- a classification which did not exist when Ainokura and Suganuma villages were designated as Historic Sites. In the following year, 1976, Shirakawa-Mura established the Preservation Regulation, officially designated the district, drafted the preservation plan and commenced the actual preservation work. In the same year this district was selected by the national government as an Important Preservation District for Groups of Historic Buildings. Subsequently, in spite of the fact that in most other villages the Gassho-style houses were nearing the point of extinction, with the population and the number of households noticeably on the decline, Ogimachi village remained stable during this period without any significant change. As mentioned above, the different designation categories of the three nominated properties -- Ainokura and Suganuma as Historic Sites and Ogimachi as a Preservation District for Groups of Historic Buildings -- were the result of the revision of the preservation law and the newly-introduced category of Preservation Districts. For nomination to the World Heritage List, however, it was decided to unify the system of classification by introducing the new system, under the category of Preservation Districts for Groups of Historic Buildings -- to both Ainokura and Suganuma Villages. In August 1994 the local governments of both Taira-Mura and Kamitaira-Mura established Preservation Regulations and drafted Preservation Plans, and all preservation work from this point on will continue under the new system. In Shirakawa-Mura, just outside of Ogimachi Village to the southwest, an outdoor museum was started by gathering together a number of abandoned Gassho-style houses from other villages in the area. This museum has served as catalyst for the preservation of the living historic village. In Kamitaira-mura, outside of Suganuma Village the village to the southeast a youth training center was established, also using abandoned Gassho-style houses which were brought in from other areas. Young boys and girls stay in these houses to learn the experience of living in a traditional environment.