Structure of the Codes  (Introduction)

The geographic area codes are seven-character strings, consisting of lowercase alphabetic letters and embedded or trailing hyphens.  The code list shows only the alphabetic characters and embedded hyphens.  The trailing hyphens that are added to codes shorter than seven characters for input into the MARC record are not shown in the list.

The codes are constructed to provide a hierarchical arrangement of geographic and political entities.  There are three levels possible in the codes.

First Level:

Most codes are at the first level and represent continents, regions, geographic features, and some national level political jurisdictions.  A first level code consists of one or more lowercase alphabetic characters.  For example,

A list of single character first level codes appears in Places Represented by Single Character Codes.  The following seven first level entities are divided at the second level:

Second Level:

Second level codes represent regions and national level political entities located within the entity represented by the first level code.  A second level code consists of a first level code, followed by one hyphen, followed by the code for the second level entity.  At the second level, a two letter code generally represents a country, and a three letter code represents a region within a country.  For example,

The following five second level entities are divided at the third level:

Third Level:

Third level codes represent first order political divisions of countries represented by a second level code.  A third level code consists of a first level code, one hyphen, a second level code, one hyphen, and a third level code.  Third level codes always consist of two lowercase alphabetic characters.  For example,

See also:

Introduction