Recommendations: Long term/Seasonal Pitches?

Hello, now that we have our caravan we would like to make the most of it and have it sited somewhere close to home (Mold, flintshire) so I can nip back for work. I have been looking for a few weeks but struggle to find somewhere. We have 2 boys 3 & 9yrs. We are looking for :-

A long stay June to end Sept (4months)

Fields/large grass area to run free and play games

Trees to climb/stream to paddle in

Cycling allowed, maybe a play area!

Does anyone know of such a site?? Thanks