The Queen will today visit the ceremonial military unit responsible for firing gun salutes in her honour.
The monarch will tour the base of the King’s Troop Royal Horse Artillery in Woolwich.
The south-east London suburb is where Drummer Lee Rigby, 25, was killed last Wednesday as he left the Royal Artillery Barracks where he was based.
Hundreds of flowers have been tied to the military base’s railings as a mark of condolence by well-wishers.
The King’s Troop Royal Horse Artillery is a mounted, ceremonial unit that fires gun salutes on royal anniversaries and state occasions, and provides a gun carriage and a team of black horses for state and military funerals.
During Baroness Thatcher’s funeral her coffin was carried on a King’s Troop gun carriage and on Monday the unit will fire a 41-gun royal salute from London’s Green Park to mark the 60th anniversary of the Queen’s coronation.
Last year the King’s Troop moved from its former home in St John’s Wood, central London, to purpose-built premises close to the Woolwich barracks where Drummer Rigby was based.
When the Queen arrives she will be greeted by the commanding officer of the King’s Troop Major Mark Edward and a rare sight - a mounted guard of honour.
The soldiers from the King’s Troop are fighting servicemen and the monarch will present two Afghanistan medals and meet families of the unit’s service personnel.
Later, the Queen will view some of the horses before watching a gun team display in the riding school and meeting more soldiers.
Before having a private lunch in the Sergeants’ mess the Queen will see horses being shod in the forge and meet the master farrier and apprentices, and tour the veterinary clinic to view horses undergoing treatment.