Dublin Castle is a major Irish government complex, conference centre, and tourist attraction. It is located off Dame Street in Dublin. From 1204 to 1922 it was the seat of the British government's administration in Ireland. Most of the current construction dates from the 18th century, though a castle has stood on the site since the days of King John, the first Lord of Ireland. Dublin Castle was first founded as a major defensive work by Meiler Fitzhenry on the orders of King John of England in 1204, some time after the Norman invasion of Ireland in 1169. It later evolved into an official residence, used by the Lord Lieutenant of Ireland or Viceroy of Ireland, the representative of the Monarch. After the signing of the Anglo-Irish Treaty in December 1921, the complex was ceremonially handed over to the newly formed Provisional Government . It now hosts the inauguration of each President of Ireland. (wikipedia.org)