Refers to a traditional Japanese castle or a Western-style castle. Often used in historical contexts.
姫路城は白くて美しい城です。
Himeji Castle is a white and beautiful castle.
This castle was built in the Warring States period.
Oda Nobunaga built a castle at Azuchi.
The enemy army finally attacked the castle.
The soldiers defended the castle to the end.
A magnificent castle once stood on this hill.
城 refers to a fortified castle built for defense, whereas 宮殿 emphasizes a grand residence without military function.
城 refers to the castle building itself, while 城下町 is the town that grew up around that castle.
stronghold; citadel · base of operations; headquarters
branch castle; outlying fortification