This video - from viewer Mark Bloomfield - shows people gathering outside, as fire crews tackle the blaze on the National Library of Wales' roof.
It is thought that nobody will be allowed back inside the library until tomorrow.
Workers were all evacuated after the fire broke out.
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Not a bad start to the weekend, bright spells and showers for most of us.
None of the people onboard the boat had been wearing a lifejacket. They were spotted clinging to the hull of their upturned boat.
Staff at seven museums in Wales are taking strike action this weekend over plans to cut their pay.