Mount Stewart House

Country house near Greyabbey, County Down, Northern Ireland. The oldest part of this Classical 1820s house dates from the early 1800s, or possibly as early as the 1780s, when the 1st Marquess of Londonderry built a modest house designed by the English architect George Dance the Younger. Three rooms and a staircase and balustrade of the original house still survive. It was enlarged in the 1820s to its present size, the architect being William Vitruvius Morrison. In the grounds is one of the finest 18th-century garden buildings in Ireland, the octagonal banqueting house known as the Temple of the Winds.

The house was the childhood home of Lord Castlereagh (1769–1822), member of Parliament for County Down, who helped steer through the Irish parliament the 1801 Act of Union, that created the United Kingdom of Great Britain and Ireland.