Quiet place to sit in Cardiff centre at teatime?

[TBLCardiff14]

I need somewhere quiet to wait in Cardiff city centre (either Bay or Bute Park area) between 5pm and 8pm on a Tuesday evening. The libraries seem to be closed then. All ideas gratefully received!

In the bay, I would suggest the Wales Millennium Centre. There are lots of areas of seating in there, and it's quiet enough until around 7pm, when I would guess it fills up on a performance night.

Not sure in the City centre. The main library shuts at 6, the museum at 5. Joh Lewis coffee shop is quiet in the evening, and open until 8pm, but I'm guessing that's not what you are looking for?

Thank you! Problem resolved itself in the end, but I will remember your recommendations for next time.