ishiganto, talismanic stone tablets, are one aspect of so-called traditional geographical thoughts or outlook. Found not only in Okinawa, ishiganto spread to the Amami Archipelago, which is only natural considering the archipelago was once a part of the Ryukyu Kingdom, and areas throughout Japan.
In China, it was a commonly thought that T-intersections and four-way intersections were rife with evil spirits, and ishiganto were placed at such locations to ward off these evil spirits. However, the origins of this custom are unclear.
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