Gusuku

Gusuku (グスク, 城^?, Okinawan: gushiku) often refers to castles or fortresses in the Ryukyu Islands that feature stone walls. However, the origin and essence of gusuku remain controversial. In the archaeology of Okinawa Prefecture, the Gusuku period refers to an archaeological epoch of the Okinawa Islands that follows the shell-mound period and precedes the Sanzan period. Many gusuku and related cultural remains on Okinawa Island have been listed by UNESCO as World Heritage Sites under the title Gusuku Sites and Related Properties of the Kingdom of Ryukyu.

The Yarazamori Gusuku Inscription (1554) contains phrases, "pile gusuku" (くすくつませ) and "pile up gusuku and ..." (くすくつみつけて). Apparently gusuku in these phrases to refer to stone walls.

In the Omoro Sōshi (16th–17th centuries), the term gusuku is written as "くすく," or "ぐすく" in hiragana. Occasionally, the kanji "城" (castle) is assigned to it. In later ryūka and kumi odori, the reading shiro is also used for the same kanji. The referents of gusuku in the Omoro Sōshi are mostly castles and fortresses but are not limited to them. Some are sacred places and places of worship. In some cases, gusuku refers to Shuri Castle.

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