Suggestions welcome

milliehull

For the past 15 years we have spent 5 or 6 weeks in France but have decided that we do not want to do this anymore.  We are looking for suggestions for a site within 2 to 3 hours drive from Peterborough for a couple of weeks end of June/beginning of July. 
OH would like a beach within striking distance if possible.  We have only ever done short breaks in the UK in the past but now want a site where we would be happy to stay for longer. Any recomendations?