The history of Ireland's struggle for independence is to a great degree housed in Europe's largest unused prison. Kilmainham Gaol was closed by the new Irish Free State shortly after independence was reached. For 128 years it housed prisoners. It was an unsegregated prison with men, women and even children (the youngest thought to be 7 years old) in 92 square ft. cells with 5 people per cell.
Dublin hotels in the city centre of Dublin are within a few minutes of Kilmainham Gaol. Items such as the death mask of Robert Emmet, and the history of the Irish rebellion and struggle make this a must visit in Ireland. This makes my bucket list of 1,000 things to do before I die.
The last prisoner of Kilmainham Gaol, Eamonn De Valera later became the Prime Minister of Ireland and then the President of Ireland. Your stop at the gaol may encourage you to more honorable goals.