Garryhill House was built by the Earl of Bessborough (Viscount Duncannon) around 1740 on the site of the ancient Garryhill castle, originally built by Art Og Kavanagh, King of Leinster . During the last decade of the fourteenth century, Art Oge McMurragh (King of Leinster) lived at Garryhill. His house would have been built of a wooden structure "of clay and wattle made", the roof would have been thatched and surrounded by a kraal-like compound, housing a sizeable community of friends and followers.

In 1394, Richard II lost his patience with Art, who had been a thorn in the side of the English for years, and decided to attack. Richard and his great army crossed the Barrow at Leighlinbridge, Garryhill was captured and went up in flames. Art and his wife were caught by surprise but escaped into the woods. In 1394, Richard II said goodbye to Garryhill to return to England.

The first Earl of Bessborough, Brabazon Ponsonby, was one of Carlows largest land owners with property holdings of 10,578 acres (in addition to approx. 24,000 acres in Kilkenny).

The ancient wall of the Garden would suggest a possible bawn. A date stone incorporated into the gateway to the Garden displays an engraving of 1696. Soon after serving as Governor General of Canada between 1931 and 1935 the 9th Earl sold the house to end 200 years of association with the Bessborough Family.

It is advised to contact the property directly prior to making arrangements to visit. Please telephone for visiting arrangements, to avoided disappointment