Health Minister Lesley Griffiths says she does not consider mephedrone use 'a huge problem' in Wales.
But she added that educating people about it now will raise awareness of the dangers and help prevent people trying the substance in future.
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Improvements include new visitor centres, medieval chapel restoration and new interactive displays.
Arriva Trains Wales is set to double capacity on some of the busiest routes into Cardiff, it's been announced.
First Minister Carwyn Jones is in north Wales today to open a new hangar at Hawarden Airport.