Since yagura was a defensive structure, as stated in the beginning, a number of yaguras were often built in a castle, such as Osaka-jo Castle around the Edo period and Himeji-jo Castle.
櫓は、冒頭にあるとおり防御のための建物であり、江戸時代前後の大坂城や姫路城などのように数も多く建てられていることが多かった。