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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Cloudy and damp evening and night with low cloud giving hill fog and patchy drizzle
A mostly cloudy and murky day with widespread hill fog and outbreaks of rain.
Official figures show areas of Caerphilly, Rhyl, Wrexham, Rhondda Cynon Taf and Bridgend to be the most deprived in Wales.