Basilica of Notre-Dame de la Garde, Marseille
Upper Church, Interior decoration detail
The golden mosaic decoration creates the most striking effects.
The fascinating details of the decoartive scenes and objects, the materials used, and the long and difficult restoration from 2001 to 2008 are fully dealt with in these Wikipedia entries:
fr.wikipedia.org/wiki/Basilique_Notre-Dame-de-la-Garde (French)
en.wikipedia.org/wiki/Notre-Dame_de_la_Garde (English)