Having no car we got to castle coch taking a train from Cardiff and walking across the village and up the hill. To walk up the hill you have to be fit enough, if you're not used to it, it may be very tiring.
Once you get to the castle, you have to pay a 3£ ticket and look at the nice frame of the castle, the rooms and all that, but the whole visit won't take longer than half an hour and, more important fact, it's not the real deal. The castle is just a Victorian-version of a proper 13th century castle rebuilted in 19th century. Very nicely kept, very clean, not to expensive to visit, very relaxing surroundings, but not the real deal.
Anyway i felt that 3£ was fair enough and i didn't feel cheated. Just not expect something authentic.
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