Completed after almost 20 years at a cost in excess of £80,000 - the equivalent of £45 million in today terms.
In 1610, Sir Archibald Acheson, who was Secretary of State for Scotland, received a 1,000 acre grant of land in Armagh from King James I. At that time, the Achesons owned Gosford in East Lothian. When, in 1776, another Sir Archibald Acheson was made a peer, he took Gosford as his title, and this was the name given to the family’s chief estate near the town of Markethill. “A sumptuous and stately structure…” When Thomas Hopper was entrusted with the design of Gosford Castle in 1819, it was his first major project using Norman architecture. Its style is known as a Norman Revival castle due to the numerous ideas and influences that Hopper gleaned from original Norman castles and used in the construction.
The massive hewn blocks of granite that form its walls were drawn from the Mullaghglass quarries outside Newry, and pink Armagh marble was used throughout the interior. The central element of Gosford Castle is the keep. It dominates the rest of the castle, looming above the entrance and tying together the other smaller blocks of towers and buildings. However, the interior of the Castle was aimed more at comfort than with keeping with its Norman Revival exterior. There were 197 rooms in the Castle, making it the largest house in Ireland. Central heating warmed its vast reception rooms and guests were lavishly entertained. In its heyday in the late 1860s, it was described by one visitor as “ …a wonder to behold, with its comfortable apartments, advanced plumbing and dining table profusely covered with every delicious viand.”
When the Achesons first settled in Ulster, they built a strong castle at Cloncarney around 1617, but it was destroyed in the Williamite wars of the 1640s. In 1728, the manor house which replaced it hosted the celebrated author and poet, Jonathan Swift, famous for 'Gulliver's Travels'. Swift wrote poetry at the Achesons' and a number of his poems make mention of the family, their demesne and the area around Markethill.