Postal Code: 306-0000

with check digit: 082040
When there is not a mention以下に掲載がない場合
Koga-shi古河市
Ibaraki-ken
(aka: Ibaraki, Ibaraki-ken, Ibarakiken)
茨城県

*1 JIS area code is identification code for cities,towns and villages. Maintained by JISC - Japanese Industrial Standards Committee.