Languedoc
Marseillan Plage: Yelloh! Village les Mediterranees

Yup been here
this is a two part site
Charlemagne across the road and this one on the beach side

both have swimming pools and campers are identified with wrist bands
You don't say what time of year you are planning to go and personally for only 3 weeks I would only go for a couple of long stays and one night stopovers on the way down and back

Got some pictures herehttp://s78.photobucket.com/albums/j115/Madcaravanner/France/ take a look at the one of my wife and also the one of my feet
these were September last year

Hi, went to Marseillan Plage last year. We went the first two weeks in July. Weather was hot and sunny with only 1 rain shower the entire time. Pools were good but busy. The nightly entertainment comprised of different themed shows and were a good way to pass a few hours.
The site is within a short walk to the shops and restaurants and there is a hypermarket 10 mins away by car.
There is plenty to do and see in the region and the beaches were good if you just want to soak up the sun.

Many of my family have been to La Baume and have gone back again and never had a bad holiday there yet.
If you do want to go try Leisure Direction they use Keycamp vans and tents but are much cheaper especially at the start and end of season.
taxi329