A fire has destroyed all the main structures of Shuri Castle, a Unesco World Heritage site on Japan's southern island of Okinawa.
Firefighters battled the flames for more than 10 hours, extinguishing them by Thursday afternoon. No injuries have been reported so far.
The wooden castle, built 500 years ago, was almost completely destroyed during World War Two.
The current structure is a reconstruction.
The castle served as a campus for Okinawa's largest public university until the 1970s, and has been a popular tourist attraction since.
Razed to the ground
The fire started just before 02:40 local time on Thursday (17:40 GMT Wednesday). It is still unclear what might have triggered it.
More than 100 firefighters were called to the scene, but one police officer said fire fighters struggled to contain the fire due to strong winds.
"The many wooden structures and the [recently reapplied] lacquer may have also had an effect," the unidentified officer told the Asahi Shimbun newspaper.
The fire was eventually put out at around 13:30, but all seven key buildings of the castle were burnt down.
Shuri Castle, which was was once the seat of the Ryukyu dynasty, sits on top of a hill overlooking the city of Naha - Okinawa's capital - and is surrounded by curved stone walls.
One resident said the castle was seen as "god-like".
"To us, the Shuri Castle is a god-like existence," 84-year-old Toyoko Miyazato told the Asahi Shimbun. "I am so sad I don't know what to say."
The city will now "do everything in [its] power" to deal with the fire and its aftermath, its Mayor Mikiko Shiroma told public broadcaster NHK.
According to Okinawa's tourism site, the castle burned down three times during the Ryukyu Dynasty and was again destroyed in World War Two during the Battle of Okinawa.
Until Thursday's incident it was the largest wooden building in Okinawa.
The castle had been scheduled as a stop on the 2020 Tokyo Olympic torch relay route.
Horror twice in a lifetime
By Sakiko Shiraishi, BBC News Japan
The Ryukyu dynasty was a kingdom that thrived on maritime trade, connecting countries in the region. Shuri Castle, though it had architectural influences from China and Japan, was at the centre of this unique Ryukyu culture.
But in 1879, the king was banished from the castle and the dynasty was annexed to become Okinawa prefecture.
The castle was completely destroyed in WW2 by American forces in 1945. Many documents and artefacts, which could have helped in the reconstruction, were also lost.
The current castle was rebuilt and opened to the public in 1992.
It was registered as a World Heritage site in 2000 and was the site for the Okinawa Summit in the same year, appearing in commemorative 2000-yen notes.
From Ryukyu to Japan, war to peace - Shuri Castle has been there through everything, and was a symbol of identity for the Okinawa people.
Those who saw the end of WW2 in Okinawa have seen the Castle burn twice in their lifetime. Their sorrow is beyond imagination.