also: ひらさんじょう
noun
hill castle in the plains; flatland-mountain castle
A Japanese castle built on a hill or low mountain within a plain, combining features of flatland and mountain castles. Contrasts with 平城 (ひらじろ, flatland castle) and 山城 (やまじろ, mountain castle).
See also: 平城 (ひらじろ) · 山城 (やまじろ)
姫路城は平山城の代表例です。
Himeji Castle is a prime example of a hill castle in the plains.
平山城は、平野の中の小高い丘に築かれることが多い。
Hill castles in the plains are often built on a low hill within a plain.