Next week I will be away for a fortnight. 
Mrs Red & I will be going campering in Welsh Wales. We will mostly be pottering about somewhere along the coast between Cardiff and Rhyl. 
Suggestions for things we should see & do would be most welcome. 
I hope you are well Tom.
I am glad you have decided to holiday in the principality you will feel very much at home as i think half of England is here on holiday as well! The only problem with the grockles is when they pay there £6.20 to come in to Wales they leave the ability to reverse a car in the booth with there £6.20.
To the mater at hand were to go in Wales! I see the Cement man sent you thirty miles inland when you said you going around the cost of Wales he has a point Lake Vyrnwy is a very nice spot and worth a visit.
My first recommendation is  St Fagans  open-air museums and Wales's most popular heritage attraction. It stands in the grounds St Fagans Castle, a late 16th-century manor house donated to the people of Wales by the Earl of Plymouth. It has a working 18th century smithy a woollen mill and many other attractions 
http://www.museumwales.ac.uk/en/stfagans/
Next the Glamorgan coast line from Cardiff to porthcawl a great place to walk this web site is good 
http://www.glamorganwalks.com/nashpoint.htm
Then if you pop in to Pembrokeshire the coast between Tenby and angle is a nice walk too 

You start here
Tenby
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there's stackpole and the greengate and St Govans chapel


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you may see some off these

and watch where you park
http://youtu.be/YyQAS-cmhWY(note the cattle don't notice the noise)
and this is where Harry Potter and Robin hood were filmed

and around the corner you have this!

I hope this has been some help.
if you and the good lady fancy a beer if your around the cardiff area give us a shout
Dai