The British Overseas Territory of Gibraltar has introduced the postal code GX11 1AA.
[1][2] This is pending the introduction of a postcode system similar to that used in the United Kingdom.
[4] The postcode is not required for local mail.
The Royal Gibraltar Post Office has divided the territory into fourteen postal zones known as 'walks' or 'districts', each with a number or letter as well as a name,[5] but these are for internal use and not encountered in addresses.
They are separate from the Major Residential Areas, used for statistical purposes.