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Longest. Name. Ever. Longest. Name. Ever. Have the city of Llanfairpwllgwyngyll in your empire.

A reference to the infamous Comic Book Guy quote, "Worst. [Insert Noun.] Ever."

Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch is well known as the longest place name in Europe and also is one of the longest in the world, having 58 letters.

Building this city must be done without the "Rename" function because "Llanfairpwllgwyngyll" is larger than the name field. It can take up to 33 cities founded to get it. However, you can rename captured cities with Celtic names, and newly settled Celtic cities will take the next Celtic name on the list. This will allow you to capture up to 32 cities and have the 33rd founded with a Celtic Settler to receive the achievement.