This was inside Saint-Chapelle Cathedral in Paris.
It's tiny by comparison to Notre Dame, but so so pretty inside with floor to ceiling stained glass windows. It's only a few blocks from Notre Dame, too.
Something special we learned about this cathedral was that the stained glass is all original. They took it down and stored it under the Lourve to protect it during WWII.
@shesnapped That tour guide who gave us Paris history on the Seine cruise was so stinkin' knowledgeable. It was really an awesome tour all around! Most everything we self toured but the one time we had someone telling us stuff was pretty awesome.