Deteriorating Japan castles face high costs, debates over renovation

TOKYO – Several Japanese castles with wooden structures dating back to the feudal era were destroyed during World War II. Although they were later rebuilt using steel-reinforced concrete, they have deteriorated over time and have become more susceptible to earthquakes.

Some local governments have closed the castle keeps long cherished by locals and are planning either to repair the concrete structures or restore the original wooden constructions. But the municipalities are facing problems with high costs, while debates over the two options stand in the way.

Hiroshima Castle’s five-storey reconstructed keep in western Japan, believed to have been built in the late 16th century by samurai warlord Mori Terumoto, closed in March because it was not sufficiently reinforced for earthquakes.

Before closing, the historically symbolic building attracted many locals and tourists.

A 35-year-old visitor who came to the castle in Hiroshima with his family said that “although there are various options, I would prefer it if we could take a tour inside” after a refurbishment of the keep that once had displays on local samurai culture.

The original keep was destroyed in the 1945 US atomic bombing and rebuilt using reinforced concrete in 1958. It had functioned as a museum, but after decades, the exterior walls began to crumble and there was a leaky roof, according to a city official.

A fiscal 2019 survey identified the castle as being at risk of collapse in the event of a major earthquake.

The city is planning two options: repairing the concrete keep or reconstructing the wooden structure. During discussions involving experts, some argued that a wood-reconstructed castle could function semi-permanently if it undergoes repairs.

But the path to realising such reconstruction remains uncertain. It would require time and money as the city estimates construction of a wooden keep would not be completed earlier than fiscal 2049, with costs reaching as high as 19.5 billion yen (S$157 million).

Other reconstructed concrete castle keeps, which are called “tenshu” in Japanese, are also facing the need for repairs as they reach the end of their useful life and earthquake reinforcements become weaker.

Nagoya Castle’s concrete keep has been closed since 2018. The city of Nagoya plans to re-create the original wooden structure from the 17th century by demolishing the tower built in 1959. But rebuilding has not yet begun due to debates over the city’s plan not to install lifts that could damage pillars and beams.

Discussions are under way in the western city of Wakayama over whether to renovate the concrete tower of Wakayama Castle or re-create the mediaeval wooden structure, which was razed in an air raid during the war. The concrete keep from 1958 remains open, with additional safety measures being implemented.

Meanwhile, Okayama in western Japan, which opted for renovation of Okayama Castle’s concrete keep and conducted major repair work between 2021 and 2022, saw an increase in visitor numbers of about 100,000.

The renovation included improving earthquake resistance, facilities for the disabled and the elderly, as well as enhanced immersive exhibits and video guidance. The costs, including those for other facilities of the castle, amounted to 1.8 billion yen, according to the city.

“The castle tower is a symbol of the city. Having it disappear even temporarily during reconstruction was never considered as an option,” a city official said.

Yoshihiro Senda, a castle archaeologist and professor at Nagoya City University, said: “Although reconstructing a structure with wood is extremely costly, it allows visitors to get a better feeling for what the original site look like, enhancing the intrinsic value of historical landmarks.” KYODO NEWS