In Summer, we're doing a road trip to Avignon, and I've insisted we come back by the Millau viaduct. The Other Half says she will be unimpressed by the bridge, so I thought I'd try to find something else for her.
Just a late thanks to all above. I've got an evening's Googling ahead of me to check all of your suggestions. Caves and the gorge definitely sound good, and would be on the way.
I'll check Trip Advisor unless anyone can recommend a specific restaurant?