二女 Castle (二女所) was built by 徳川 leyasu as the 京都 residence for himself and his successors. The palace building now known as 二の丸("secondary castle"), was completed in 1603 and enlarged by Ieyasu's grandson Iemitsu. It survives in its original form and is famous for its Momoyama architecture, decorated sliding doors and floors that squeak like nightingales when someone walks on them (a security measure against intruders). lemitsu also added the 本丸 ("main castle") including a five storied castle tower to Nijo Castle. However, the original honmaru structures were destroyed by fires in the 18th century, and the present building was moved there from the Imperial Palace in 1893.