A lovely postcard I received earlier this year from the 'British Isles RR' on the Postcrossing forum.
On this card you can see the Welsh national dress. Eunice, who sent me this card, tells me that little girls wear it on Saint David's day, March 1, at school. I don't know if it's worn on other occasions as well, but Matt's mum was born in Wales and she told me that when she went on a school trip to Norway, they all had to wear these dresses. She didn't seem to be too happy about it at the time... ;)