Gjennomsnittlig GPS-koordinater for postnummer 300-0831: 36.064, 140.186
Notering byer:
>> Koiwata 300-0831, Ibarakiken, Tsuchiurashi, GPS-koordinater: 36.0643,140.1863
Notering byer:
>> Koiwata 300-0831, Ibarakiken, Tsuchiurashi, GPS-koordinater: 36.0643,140.1863