The Queen and Duke of Edinburgh will attend the Royal Marines' 350th anniversary beating retreat tonight.
The event is traditionally held in celebration of the birthday of Philip, who is captain general of the Royal Marines.
This year, beating retreat will celebrate both the Duke's birthday and the 350th Anniversary of the Royal Marines.
Philip will take the salute while the Queen watches the ceremony from within the Horse Guards Arch at Horse Guards Parade, central London.
The event forms part of a busy schedule of UK-wide celebrations to mark the anniversary known as RM350.
More than 400 military personnel and musicians are expected to take part in the pageant.