Leinster House is the home of the two houses of the Irish Oireachtas (parliament), the Lower House, the Dáil, and the upper house, the Seanad. Built in 1745 for the Duke of Leinster, the house was sold to the Royal Dublin Society in 1815 who in turn sold it to the State in 1924. Designed by Richard Cassels it was to look like a townhouse from the Kildare Street side and a county house from Merrion Square. It stands between the National Library and the National Museum.