site recommendations for st davids, wales

We are travelling to Wales in our 24ft motorhome and once parked up we leave it and use public transport, walk or bike. We have booked 2 nights in Cardigan (we can get to Fishguard on a bus here), and plan to travel as far as Tenby and eventually head back home up north. Please could anyone recommend any easy to get to sites we can use as a base, so we can see or travel easily to St David's and all the lovely places along that area (up to Tenby)

Thankyou