Shizu no iwaya (静之窟)

Shizu no iwaya has its origin in a folklore in the myth of the development of the land by Okuninushi no Mikoto and Sukunahikona no Mikoto, and the place was depicted in a Oishi no Suguri no Mahito's poem in Manyoshu (Volume 3-355) "Onamuchi and Sukunahiko lived in Shizu no iwaya; how many generations that have been passed by?"
According to "Shoku Nihongi" (Chronicle of Japan Continued), the author Oishi no Suguri no Mahito was appointed to Mino Shosakan (officer of Mino Province) in 738 and Ge-jugoinoge (Jugoinoge (Junior Fifth Rank, Lower Grade) given to persons outside Kyoto) in 750.
The location of Shizu no iwaya is unknown, and there are several theories as follows:

The Stone Treasure Hall of Oshiko Jinja Shrine (Takasago City, Hyogo Prefecture)
Shizu no iwaya (Oda City, Shimane Prefecture)
Atsutane HIRATA's "Koshiden" (Commentary on Ancient History) identifies this as the place of Shizu no iwaya.

Iwaya in Shizunoiwaya Jinja Shrine (Onan-cho, Shimane Prefecture)
Norinaga MOTOORI's "Tamakatsuma" (a collection of essays) identifies this as the place of Shizu no iwaya.

[Original Japanese]