Just a word of warning from one dad to another.
Having persuaded the wife that a week camping in Font would be the perfect family holiday with our 1yr old we booked into Les Courtilles du Lido campsite (on a UKB recommendation no less!)
Take a look at the map on their website.
http://www.les-courtilles-du-lido.fr/images/VeneuxPlan.jpg Notice that massive rail intersection 400m south of the site? We did!
Heavy good trains rattling through there woke us ALL up several times a night every night!
Such a shame as everything else about the site was perfect.
Personally I'd look elsewhere.