A Saku (柵 – also pronounced ki) is a type of stockade or palisade constructed in frontier regions.
Notably, most were constructed between the 7th and 9th centuries in northern Honshu to defend against the northern Ezo People, as well as to provide administration to the surrounding areas. Known Saku are Nutari no Ki and Iwafune no Ki, with larger cities also containing Saku. Areas known to have had Saku are Tagajō, Izawajō and Akitajō.1
1. Kodansha. (1993) ”Japan: An Illustrated Encyclopedia”. Tokyo: Kodansha Ltd.
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