This masterpiece of 17C Japanese architecture is said to resemble a graceful "white heron in flight", even though it was built solely for defensive purposes with a five-storey central keep, defensive towers, an intricate maze of paths designed to confuse intruders and fan-shaped ramparts... The castle was however never attacked during its four centuries of existence. Since 2015, after a massive renovation programme, it is possible to explore the whole fort and go to the top of the main keep, which commands a splendid panorama of the town.