The Queen and the Duke of Edinburgh have arrived in Northern Ireland at the beginning of a three-day visit.
The Queen attended a reception at Hillsborough Castle
The royal couple will carry out a number of engagements in Belfast and at Hillsborough Castle over the next few days.
The visit will also include the Royal Maundy Service at St Patrick's Church of Ireland Cathedral in Armagh on Thursday.
The Queen attended a reception at Hillsborough Castle.
Northern Ireland Secretary Shaun Woodward said the visit was "an enormously significant and historic occasion for everyone".
"In this new era of political stability and optimism the people of Northern Ireland, who continue to embrace our shared vision of normality, will see a Royal Maundy Service take place here for the first time ever in the historic City of Armagh," he said.
William Hall, the Lord-Lieutenant of County Down, greeted the Queen and the Duke on their arrival at Hillsborough Castle and went on to introduce the Northern Ireland Secretary.
In her first engagement at Hillsborough Castle, the Queen met more than 300 members and workers from the Territorial Army.
The event was to mark the organisation's centenary.
On Thursday, the Queen will hand out Maundy Thursday alms purses to people in Armagh, part of an ancient ceremony held each Easter.
She will present 82 men and 82 women with the traditional Maundy purses, which is to represent her 82nd year.
The presentations are given in recognition of people's services to both church and community.
The Queen has attended 52 Maundy Services at more than 40 cathedrals during her reign.
It is held on the Thursday of Holy Week to mark Christ's Last Supper and used to include a symbolic washing of feet. This was discontinued in the early 1700s.
The last time the Queen was in Northern Ireland was in June 2007 at a party for the community and voluntary sector in Coleraine, County Londonderry.
She was also in Northern Ireland in October 2006 for the final review of the home battalions of the Royal Irish Regiment before they were disbanded last summer.
The Queen held a meeting with Irish President Mary McAleese for the first time on the island of Ireland in December 2005.