Will be me, DS(12) and DD(8) we walk a lot so doesn't need to be very close to public transport, just within 5 miles and on a safe route (although closer is great).
Will look at anywhere in the UK, we're in Kent but DC enjoy travelling and we are bored of going to the same 3 sites all the time.
Campsite needs to allow fires (happy to pay for a fire pit/logs) have a toilet and a tap. we don't need any other facilities, we like really basic camping.
DD would quite like it to be near the sea, or at least a stream or lake she can paddle in. DS doesn't mind, as long as there are marshmallows to toast.