The original Nagoya Castle was built in 1612 by Tokugawa Ieyasu as a stronghold for his ninth son and a buffer against the western daimyo. The keep was burnt to the ground in a single American firebombing raid on 14 May 1945 — one of the largest losses of an intact major castle in Japanese history. The five-storey concrete reconstruction completed in 1959 is convincing from the outside and houses a museum about the castle's history; it is, however, closed indefinitely for a wooden rebuild that has been delayed by funding and accessibility disputes.
The real reason to visit today is the Honmaru Palace beside the keep, reopened in stages between 2013 and 2018 after a 150 million dollar reconstruction using traditional carpentry and original paint techniques. The cypress floors, the gold-leaf sliding screens by Kano-school painters, and the carved ranma transoms are extraordinary — the closest thing in modern Japan to walking through a fully intact 17th-century lord's residence. Allow at least two hours for castle and palace together.