horsestache we are lucky to have a caravan in the family here
http://www.kellingheath.co.uk/.
It is an absolute dream, set in the woods, you can hire out the static caravans but I am not sure how much. They are all modern and well equipped.
The surrounding area is very unspoilt, near the sea but not tacky. You can buy fresh crab from locals and it is so relaxing.
Perfect for dogs, the place is built on a nature reserve. Holt is nearby , a lovely (posh though) little town. Good luck in the search.