Dyffryn House will reopen for the first time since its multi-million pound restoration. The historic house has never been fully opened to the public before, but today visitors will be able to explore its restored rooms for the first time.
Rooms on the ground and first floor will be open to allow visitors to enjoy views of the garden.
In January, the National Trust took over management of the house and gardens on a 50-year lease.
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It's judgement day at the Millennium Stadium as Cardiff Blues take on the Ospreys and the Newport Gwent Dragons face the Scarlets.
Showers expected throughout the day especially in the north. Drier and brighter elsewhere but cooler than in recent days.
Most places will become dry overnight, although it will remain generally cloudy with patches of hill fog.