Nagasaki City has announced a proposed plan that would provide priority repairs and maintenance to several buildings on Hashima Island (aka. Gunkanjima), including former mineworkers’ housing and school buildings.
The five buildings that were selected are considered to be in a condition where they can still be maintained to some extent. The plans include rust-proofing and adding additional reinforcing to the structures, although exact details have yet to be decided. Two other islands, which also have traces of coal mining activities, may also be included in the final plan which is expected to be submitted to the Nagasaki Mayor in May.
The buildings include:
- Building 16 (c1918, 9-storey, RC, 66-unit apartment building)
- Building 17 (c1918, 9-storey, RC, 54-unit apartment building)
- Building 65 (c1945, 9-storey, RC, 317-unit apartment building)
- Building 3 (c1959, 4-storey, RC, 20-unit apartment building)
- Elementary and middle school building (c1958, 7-storey)
Building 3 was built for senior-ranking staff at Mitsubishi. It was the only apartment building to contain indoor baths. Building 65 is the largest apartment building on the island. It was built during WWII, which was a time when building materials were in short supply and construction of reinforced concrete buildings across the rest of Japan was halted.
The city is preparing to apply for a World Heritage designation later this year.
Hashima Island was nicknamed Gunkanjima (battleship island) because of its resemblance to a Japanese warship. The 63,000 sqm island is located 17.5 km south-west of Nagasaki Port.
Although the existence of coal was known in the late 1700s to early 1800s, it would be another 100 years before serious efforts were made to extract it. In 1890, Magotaro Nabeshima, a feudal lord, sold the island to Mitsubishi for 100,000 Yen. Shortly after acquisition, Mitsubishi began excavating mine shafts, installing water distilleries and opened up an elementary school. Land reclamation from 1897 to 1931 saw the island gradually increase in size.
The original buildings were mostly 1 and 2-storey wooden structures, but in 1916, Japan’s very first reinforced-concrete apartment building was completed on the island. Building 30 has 7 floors and 140 apartments. It was originally built with 4 floors, but additional floors were added shortly after completion. This is Japan’s oldest existing apartment building. However, due to a relative lack of knowledge about concrete construction methods at the time, poor materials and a harsh environment, the first four floors of the building deteriorated quite rapidly. In 1953, reinforcing materials from the upper floors were switched with the weaker materials from the lower floors to provide additional reinforcement to the concrete. Other buildings on the island have also suffered severe deterioration over the years. A shortage in building supplies meant that concrete was made using sand with high salt levels.
The population of the island peaked at 5,259 in 1959. The population density reached the equivalent of 83,600 people/km2 for the island, making it the most densely populated area on the planet. For comparison, Singapore currently has a population density of around 7,301 people/km2 while Tokyo has 6,000 people/km2.
In addition to the mines and worker accommodation, there were schools, shops, a hospital, temple, movie theatre, barbershop, salon, pachinko parlour, mahjong club and a snack bar. Due to a shortage of space, a crematorium and cemetery were built on the nearby Nakanoshima Island.
In the 1960s, a shift to oil saw a decline in the coal mining industry in Japan. In 1974 the mine closed and the remaining occupants left the island for good. In 2001, Mitsubishi Materials Corporation donated the island to Takashima Town (which later merged with Nagasaki City).
The island was partly opened up to tours from 2009. In the first three years, over 275,000 visitors toured the island. The tours are thought to have generated as much as 6.5 billion Yen for the local economy.
The Nikkei Shimbun, March 24, 2015.
The Sankei Shimbun, March 24, 2015.