Hyphens, no hyphens: what is correct spelling of French commune names?

Reader question: I sometimes see names of communes written with hyphens and sometimes without. What is correct? J.A.

The Association des Maires de France states that the official rules say when the name of a commune, or other local authority, is composed of several words, they should all be connected by hyphens. So, for example: Saint-Germain-en-Laye. One exception is the definite article at the start of a name, eg. Le Mans. There is also no hyphen after contractions such as d’ and l’.

The rule helps make it clear the name relates to an administrative area and nothing else. The association regrets, however, that some new communes get this wrong when registering their names.

Words must also be capitalised, apart from articles inside the name, and prepositions.

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