10th anniversary Europe trip in September

We are a couple in our 40s who are planning a mid to late September Europe trip without our kids for our 10th wedding anniversary. would ideally like to try a place we haven’t been.

Places we’ve been together: paris/Strasbourg, slovenia, Italy (Venice, Tuscany, Rome and Positano), Luxembourg. we’ve also been to (individually): Spain, Amsterdam, London, Belgium

We are open to locations but really would just love a wonderful trip and ideally decent weather. I know this is vague but any help would be much appreciated!