Hi Sandra
There are quite a few around. For someone who’s new to Cardiff and going on your own, the best bet is probably the biggest night, Bar Risa, next to the Millennium Stadium, on Thursday night. Classes start just after 8pm and free dancing goes from around 10-12. It’s good fun, though it can get very hot.
If you’re going with a friend La Tasca in the Brewery Quarter off St Mary Street on a Saturday night (11-2) usually has a good party atmosphere with a mix of dancers and non-dancers.