also: とうじょう
noun, noun or participle which takes 'suru', intransitive verb
attendance at a castle; going to the castle
Historical term referring to the act of going to a castle, especially in the context of a lord or samurai attending upon a superior. Used as a noun or with する to mean 'to go to the castle'.
家臣は毎朝登城して主君に仕えた。
The retainers went to the castle every morning to serve their lord.
登城の際に
Formal attire was required when attending the castle.