Etymology and distribution of 極殿.

Gokuden 【極殿】^{レベル2
About 10}  The Japanese surnames etymology dictionary.

Shimane-ken , Kagoshima-ken , Miyazaki-ken .

① Topography . Shimane-ken Goutsu-shi In the ruined town, tells that Mr. Sawa of Chiba-ken Northern Ibaraki-ken Southwest part (formerly Shimosa) came to the era of warring States and added "Tsu". 沢 Sawa reference.

② Topography . Kagoshima - ken Shibushi - shi From Ariakemachi Nogami from Sawazu Mine gate of the gate division system which was in the Edo period. The gate name is from Sawa, a bamboo field and Mine.