LONDON - The Queen Elizabeth II opened a new era in Anglo-Irish relations on Tuesday as she began a four-day visit to Dublin that marks the historic reconciliation of both nations. Defying a dissident Republican bomb threat, the 85-year-old monarch stepped onto Irish soil shortly before midday wearing emerald green. She stood proudly as the national anthem was played alongside an Irish rebel song outside the official home of the Republic's president. The rendition of God Save The Queen was followed by the Irish national anthem - The Soldiers' Song -which was sung by freedom fighters during the 1916 Easter Rising. There was then a 21-gun salute and an Air Corps flypast. The gesture was replicated at Buckingham Palace where Changing of the Guard was marked with the playing of the Irish folk song, Danny Boy. Politicians on both sides of the Irish Sea described the visit as momentous. The Queen then inspected a guard drawn from the Irish army, navy and air force, before laying a wreath at the Garden of Remembrance. The visit - first suggested by Irish president Mary McAleese 13 years ago -went ahead despite the discovery of a "viable" bomb on a bus 15 miles from Dublin, and the threat of several other suspect packages. It was the first visit to Ireland by a British monarch since 1911. Scuffles broke out as up to 200 Republicans tried to reach O'Connell Street while there were shouts of "Queen out" at the Garden of Remembrance prior to the Queen's visit. to honour the thousands of Irish killed while their country was under British rule. But amid the biggest security crackdown in the Republic's history, the royal party received a largely warm welcome. The Queen smiled as she was shown round the presidential residence that was once home to British viceroys.