Etymology and distribution of 中古閑.

Nakakoga 【中古閑】^{レベル2
About 10}  The Japanese surnames etymology dictionary.

Mie-ken Yokkaichi-shi .

① There is a 平岡 surname.

② Korean type . Originated in Uljin County, Pyeongheeong Province, South Gyeongsangbukdo. Added "Hei" of the Heian sea on the hill. There is a record of naturalization on Hyougo-ken Amagasaki-shi on August 5, 1958. The real name is a hill. 丘 Oka reference.