Allow me to recommend a book: Ina Caro, Paris to the Past, Traveling Through French History by Train. Each chapter covers a historic site, such as a cathedrals, that can be visited as a day trip from Paris by train. She's Robert Caro's wife and research partner.

And I strongly agree with the suggestion to research and do it yourself. There's a tremendous amount of information available. I like wandering museums with a phone, so that I can do research on the spot. Google lens is good for identifying art that is not well labeled.