One thing to do is visit the surreal building called Palais Idéal in Hauterives that the postman Ferdinand Cheval built. The photos I’ve seen, and the story behind it, look very intriguing: he started with a single stone that looked intriguing to him, and over many years he built a surreal castle with stones that he found on his delivery rounds. The building is a folly, a building that is only built for decoration. But although it has no clear purpose or design, yet it is something that stands as a convincing building.
(Image source: wikipedia)