On a Road Scholar tour we went to Anglesey to see Penmon Priory and St Seiriol's Well which was a stop on the pilgrimage route to St David's in the Middle Ages. Apparently 2 or 3 trips on the St David's pilgrimage route was the substitute for one pilgrimage to Rome according to our guide. There are a couple of medieval crosses in the priory and a SheelaNaGig which remained by the front door of the church until the 1970s or so but is now moved inside in a side room with the medieval crosses.
About Penmon Priory:
http://en.wikipedia.org/wiki/Penmon
About the SheelaNaGig:
http://www.sheelanagig.org/index.html#http://www.sheelanagig.org/SheelaPenmon.htm
The medieval Misericords from the choir area of Penmon Priory are now located in the church of St Mary and St Nicholas in Beaumaris.
http://www.snowdoniaheritage.info/en/location/156/st-mary-s-and-st-nicholas-s-church-beaumaris/
There is also an Elizabethan dovecote across the road from Penmon Priory.
I found the Priory and the Beaumaris church very interesting, however, I do believe you would need to rent a car to see this area!