A dog on a lead at Caerphilly Castle
Dogs on leads are being welcomed to visit 17 historic sites across Wales, after demand from pet owners.
Historic monument agency Cadw, said it hoped the dog-friendly policy would "increase everyone's, including pets', enjoyment" of heritage sites.
Those initially open to dogs on leads include Blaenavon ironworks, Caerleon Roman amphitheatre, St Davids Bishop's Palace and Ewloe and Rhuddlan castles.
If successful, Cadw said access could be rolled out to more sites.
Marilyn Lewis, director of Cadw, said, "Dogs are great companions and often integral members of the family.
"There is no reason why they should be left out when planning to explore heritage sites across Wales."
The news has been welcomed by Clarissa Baldwin, chief executive of Dogs Trust.
She said: "This is fantastic news for all dog owners, who will now be able to enjoy Cadw's wonderful heritage attractions along with their four-legged friends."
HISTORIC HOUNDS OF WALES
Gelert, the legendary hound of Llywelyn ap Iorwerth, is credited with giving Beddgelert (Gelert's grave) in Snowdonia its name
One of the six crests - the one representing Wales - borne by Richard III, depicts a golden cradle and a silver greyhound
Possibly the most famous Welsh terrier in the world was Charlie, President John F Kennedy's loyal dog
The heritage body said owners will be expected to clean up after their dog, but poop bags, and bowls of water, will be provided on request.
Assistance dogs and their owners already have access to all Cadw monuments without restriction.
But for safety reasons some areas, such as spiral staircases, castle ramparts and exhibition areas are out of bounds for all dogs.
The first 17 sites are:
Blaenavon ironworks, Caerleon Roman amphitheatre, Caerphilly and Raglan castles and Caerwent Roman town in south-east Wales; Oxwich and Cilgerran castles, Lamphey and St Davids bishop's palaces in south-west Wales; Strata Florida abbey in mid Wales; Denbigh, Ewloe and Rhuddlan castles and Basingwerk and Valle Crucis abbeys in north-east Wales and Castell y Bere and Dolbadarn castle in north-west Wales.