Roussillon, the old ochre quarries. It was hard to get true colour in the photos - but it was certainly beautiful.
We hope that there will be a "next time" in Provence where we can visit a similar but less developed area called the Colorado of Provence. We got talking to a French couple at the end of our walk through the Roussillon quarries. Like us, they thought the time estimated for the longer walk was very much an over-estimate, and recommended Rustrel to us as a less developed and longer outing.
Roussillon is where I bought my beautiful coloured pigments as shown in THIS post.