Yeomen Warders are the colourfully-dressed bodyguards on duty at the Tower of London.
One of their main ceremonial functions is the daily Ceremony of the Keys. In this ceremony the gates of the Tower of London are secured each night shortly before 10.00 pm by the Chief Yeoman Warder escorted by an armed guard of four men.
After locking the gates, the Chief Yeoman Warder is challenged by a sentry bringing his rifle into the on-guard position.
He allows him to pass after recognising the Chief Warder as the bearer of Queen Elizabeth's keys by saying 'Pass, Queen Elizabeth's keys, and all's well'.
The Chief Yeoman Warder and his escort are met by a ceremonial guard on the Broad Steps near the White Tower, which then presents arms.
The Chief Warder concludes the ceremony by raising his Tudor bonnet and proclaiming 'God preserve Queen Elizabeth', to which all present reply 'Amen'.
The keys are then carried by the Chief Yeoman Warder to safekeeping, whilst the Last Post is sounded.
The ceremony has taken place over the same piece of ground, in war as well as peace, for about 700 years.
Although it is open to the public on application to the Tower of London for invitations, the ceremony is usually heavily booked.
While their role is usually confined to the Tower of London, the Yeomen Warders do take part in one State ceremony. At Coronations, they form a guard of honour inside the annexe at Westminster Abbey.
The State dress uniforms of Yeomen Warders are almost identical to those of the Yeomen of the Guard, but the Yeomen of the Guard can be distinguished by their cross belts worn from the left shoulder.
For everyday duties, Yeomen Warders wear a dark blue and red undress uniform.