When the Ladies of Llangollen moved into Plas Newydd it was simply a two-storey, stone cottage. Over the next fifty years (Sarah was the last to die in 1831) they gradually transformed it, turning the extension into a library, adding Gothic windows, window canopies and an elaborate porch. The whole house, inside and out, was covered in their collection of carved oak pieces much of which was put together in jig-saw fashion.
In 1876 General John Yorke bought Plas Newydd and is responsible for the timber battens on the front of the house.
The Ladies held a 'porch warming' for their close friends. Two 17th century bedposts support the roof and on either side of the door are seats with shelves above where they would have displayed items from their eclectic collections.
The imagery of much of the oak carving is taken from Classical and Biblical subjects. The porch door features emblems from the four evangelists and the above door has Old and New Testament scenes.
On a door on the west side of the house there is a carving of the Harp and Crown of Ireland and the inscription, 'Sincerity, Fidelity and Industry', which refers to the three women, Lady Eleanor, Miss. Sarah Ponsonby and their faithful maid, Mrs. Carryll.
The maid, Mary Carryll, was as much a character as the two Ladies. 'She wore high heels and a stiff dress, using a profusion of hair powder and pomandum' and was a formidable and loyal servant who had helped the women in their flight from Ireland. When she died in 1809 she left one of the fields to them which she had bought with her life savings. The Ladies erected a three sided memorial to her in Llangollen churchyard in the place where they themselves planned to be buried.