Postal codes in the Faroe Islands consist of the two letter ISO 3166 code "FO", followed by three digits: Separate postal codes are used for PO Box addresses in the capital Tórshavn and some other towns:[1] Previously, the Faroe Islands formed part of the Danish postcode system, introduced in 1967, which also included Greenland.
[2] This used the number range 3800 to 3899, and the "DK" prefix for Denmark:[3] Later on, the "FR" prefix was used:[4] When the three-digit postal codes were first introduced, they were used for PO Box addresses, alongside the existing four-digit ones.
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