Here are all the postal codes assigned to Onsan-eup. Our records often include geographical coordinates of Onsan-eup and it's corresponding postal code. In the result box below, you can find the postal code of Onsan-eup and it's location on the map if we have the location information available. Every postal code is also located in a region or a district, in case we know the district or region of the city it will too be listed in the results. All kinds of additional information we have on Onsan-eup may also be present such as geographical data, historical records or news about Onsan-eup and in general.