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Enter UN/LOCODE (United Nations Code for Trade and Transport Locations), which is maintained by UNECE (United Nations Economic Commission for Europe). The code consists of the 2-letter country code from ISO 3166-1 followed by a space and a 3-letter code for a local place. To find a code for a local place, go to the UN/LOCODE Code List by Country, click on the name of the country to find a table of local place names in the country, then find the code for the local place. For the United States, there seems to be one big table for all places as well as 5 tables broken down by letters of the alphabet. For example, to find a code for Cambridge, Mass., click on either "United States" or "{A to E}", then find Cambridge in the table. There are 11 places named Cambridge in the list; the code for the one in Massachusetts is "US JHY".
If a code is entered in locode, the values for country, region or state, and city will be entered automatically when the record is saved. Either enter a value in the box for locode or fill in the boxes for country, region or state, and city. Do not do both.
region or state
Enter code derived from ISO 3166-2, Codes for the representation of names of countries and their subdivisions – Part 2: Country subdivision code. The code consists of the 2-letter country code followed by a hyphen and up to three letters representing a subdivision, such as a state. Click on the 2-letter code for the country in the Wikipedia table (not on the name of the country), then find the code for the subdivision. For example, to find the code for Massachusetts, start at the Wikipedia page for ISO 3166-2, click on "US", which brings you to ISO 3166-2:US. The code for Massachusetts is "US-MA". Enter only the part after the hyphen, e.g. MA, as in US postal codes..
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