lots of people stay in the aires - Personally, I don't see the point of this, but obviously it is a personal choice. Motorhomes are everywhere so you will be welcome wherever you go. Bordeaux is a good area to go to - easy access via autoroutes the beaches are fine but can be crowded the french love the sea and many bordelais may leave thearea but they still return for the summer
Tunnel is quickest but much more expensive. I guess your cheapest option for motorhome towing car would be DFDS Dover-Dunkirk. Check both operators websites for prices, you can book with them online from their websites.
Don't forget to leave a review of the French and other European campsites you have visited!
We take motorhome with bikes to France and have enjoyed some great hols using just aires/France Passion sites but we cycle a lot in an area to explore then move on almost every day. Hardly ever pay for sites....sometimes we just tuck discreetly into a spot for wild camping and although it's not strictly legal, it's mainly ignored providing you're not blatantly obvious!
I'd recommend Loire region and cycling in the Loire Valley is very enjoyable. We cycled the Burgundy and Nivernais Canals last time and though it was too hot (July/Aug), it was a great experience.
This year we're touring/cycling in the Vendee area.
Up until this year, we've taken the Tunnel as it's quick and not too expensive if you book in advance but this year we're ferrying from Portsmouth to Cherbourg to cut down on the driving.
Whatever you decide, hope you enjoy the experience!
Just go for it!!
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Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.