Somewhere in the east/south-east of France

[givememarmite]

I am looking for somewhere in the east/south-east of France where we could rent a holiday place (villa/gite) to stay for a week or so. I live in Germany, my parents are in the UK and we haven't seen each other for nearly two years for obvious reasons!
As they can't enter Germany but we are all allowed to travel to France, I'm trying to find somewhere we could meet that isn't too far for us to drive to. They have a motor home and are retired so they are happy to drive further. Any suggestions of nice towns/villages to look at?

It's not a town, but Lac du Chalain, which is near the Swiss border is just beautiful. We stayed there in a static caravan with Eurocamp, but you can take your own camping stuff/motor home as well. If you do a search on the Eurocamp website it will be there, and other companies besides Eurocamp use it. It books up really early though, so might not be any room, but if you'd prefer a gite anyway, maybe look on airbnb for somewhere nearby?