You may find it difficult to book 4 nights only at that time of year due to peak season. Wareham forest would fit you bill iv they have vacancies. We have just returned from a wonderful break there.
------------- Albino, Can"t say fairer than that !
the Shorefield, or maybe it was Shorelands chain, they are quite decent, near Bournemouth, usually had spaces as well, tents, vans, pool, bar, near nice towns, simples.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets