The tenshu (with three layers, three stories and a basement) built without using toshi bashira (through pillar) belongs to the multi-layered borogata style (a type of castle tower for lookout on the building with a gabled, hipped roof) and is supported with stone walls called gobozumi (a method of piling up stone wall, piling up with deep stones of which bonder side faces front).
通し柱を用いず、各階ごとに積み上げられた天守は、三層三階地下一階の複合式望楼型で「ごぼう積み」と云われる石垣で支えられる。