Which areas cannot be done by train?

There's no place that can't be done without a car. Nothing is absolute, regardless of who says so. It might be easier by car, but so what? Virtually any village can be reached from any other by public transportation (bus, train, or combination), it might be cumbersome, but it can be done. It might take you a day and a half to get from A to B, you have to decide how important it is for you to get there and how much time you have to throw at it. You're asking a question to open to interpretation. Any response can be refuted in half a heartbeat. You're setting yourself up to eliminate too much.

Ed is right - most places can be reached by public transportation. It really depends on how you want to organise your trip. If it's mostly towns and cities, with some daytrips to some of the outlying areas, you can (with a bit of advanced planning preferably) do without a car. But if you want to explore several small villages in Provence or visit a few Loire Chateaux in a short period, I would recommend that you rent a car.

I heartily agree with Ed. To say an area can't be "done" w/o a car is an oversimplification. It totally depends on what you want to see and how long you have to see it. In Provence you can get to larger towns like Avignon, Aix, Arles, Orange, Nimes, etc by train and from there to the smaller towns by bus or combo train/bus. It will take a bit more research and planning but certainly doable. The same with the Loire Valley and Dordogne and anywhere else in France for that matter. Renting a car and driving for a few days will allow you to see a bit more in the same amount of time and gives you the freedom to explore a different area on a whim, but it's by no means required. Many many travelers never rent a car in France and are able to see what they want to see and enjoy their trips as much as those who do drive all or part of the time. Edit: sorry for the duplication, I was composing while the others were posting.

There certainly are parts of France that can't be done without a car. I certainly recall seeing several posts on this board in the last few months about villages in France that had no public transportation at all, or only paratransit.

There is a difference being between: - been able to reach point A, B or C from outside point X with some form of transportation (private car or public) - been able to travel through A, B and C on a time-convenient manner without losing much time You can reach certain places with some non-frequent on-call bus, that doesn't mean driving up there isn't much better in terms of time and access. Likewise, you can reach 99,5% of places in Europe by car, which doesn't make it a convenient or economic option for, say, visiting different points in London or Rome.

Before kids my husband and I would spend entire summers in Europe and never once rent a car. You can get virtually anywhere using public transport. Sometimes it isn't easy, and we did our fair share of walking, but it was a great adventure! You just need time and the willingness to be patient, especially in more remote areas where busses are infrequent and not always on time. Honestly, we met far more interesting people then than we do now, now that we travel almost entirely with cars. We went to every one of the regions you mentioned and had no problems. It's certainly easier with a car but certainly not impossible.