Where was Joyeux Noël filmed?
2005 film by Christian Carion
Joyeux Noël (2005) was filmed in Saint-Pol-sur-Ternoise, Barlin and Château de Brias, 3 places named in its French Wikipedia’s Préproduction section, in France. Wikidata records no filming location for it at all, so the article is the only recorded source. Each place says where its claim comes from.
Places per French Wikipedia's Préproduction section
French Wikipedia’s Préproduction section names 3 places. Each links to the sentence that says so.

