Any particular area?
In the North, I'd agree Betws-Y-Coed and Beaumaris are nice places to visit, though I've not pitched up at either.
The club site in Caernarfon seems a long drive from the town, but there's a nice countryside walk down to the shore near the castle, leading back into town.
There are some nice roads up into Snowdonia around Blaneau Ffestiniog (?).
Electric Mountain in Llanberis is well worth a visit if you're into large-scale engineering, and it's in a country park.