In 664, Sakimori (soldiers garrisoned at strategic posts in Kyushu in ancient times) were garrisoned and fire beacon platforms were set up in Tsushima, Iki, and Tsukushi Provinces, and Mizuki (Water Fortress) was built to the west of Dazaifu.
664年、対馬国・壱岐国・筑紫国に防人とのろし台を設置、大宰府の西方に水城を築造した。