Irish President Michael D Higgins arrived in Britain today for the first ever official visit by the head of the Irish state to the UK, a four-day trip symbolizing the amazing extent to which relations between the two countries have transformed in recent years.
The Queen paid a historic visit to Dublin in 2011.
This evening, there will be another first as the Northern Ireland's deputy First Minister Martin McGuinness, a former IRA commander, will sit down at a state banquet at Windsor Castle.