The Queen will celebrate the 100th anniversary of the Women's Institute (WI) when she attends the organisation's centenary annual meeting.
The Queen will be joined by the Princess Royal and Countess of Wessex at the meeting of the National Federation of Women's Institutes being staged at the Royal Albert Hall.
The monarch became a WI member in 1943 when she was still Princess Elizabeth and over the years has attended meetings at the Sandringham WI.
The WI was formed in 1915, a year into the First World War to rejuvenate rural communities and encourage women to become more involved in producing food to help combat German naval blockades.
It was inspired by an idea from Canada and was first founded in the Anglesey village of Llanfairpwllgwyngyll - famous for having Britain's longest place name.
Traditionally associated with "jam and Jerusalem", the WI has modernised in recent years.
Its most famous members - the Calendar Girls - appeared semi-nude in a fundraising calendar and met the Duchess of Cornwall and Sophie on Tuesday at a Buckingham Palace garden party held to mark the centenary.
Since January 1 2014, a specially designed centenary baton has been travelling around the UK throughout the WI's 69 federations in England, Wales and the islands to celebrate the links of friendship and community developed through the organisation.
The Royal Albert Hall will be the baton's final stop and the Queen will receive it during the event and watch footage of its journey before cutting a centenary cake.
Later in the day, Sophie will host a Palace garden party in honour of the centenary of the charity Blind Veterans UK.