Queen to light beacon in 90th birthday celebration
The Queen will light the first of more than 1,000 beacons across the UK and other countries to mark her 90th birthday later this month, Buckingham Palace has said.
The ceremonial lighting will take place in Windsor on the evening of 21 April.
The event will follow a royal walkabout in the town.
Later, members of the Army cadet force will take beacons to the top of the highest peaks of England, Scotland, Wales and Northern Ireland.
Some of the beacons will be specially built gas-fuelled structures. Others will be traditional bonfires, or braziers on top of tall wooden posts.
They will be taken by cadets to the summits of Ben Nevis, Mount Snowdon, Scafell Pike and Slieve Donard.
The Queen will be accompanied at the beacon lighting by the Duke of Edinburgh, the Prince of Wales and the Duchess of Cornwall.
Royal jubilees, coronations and birthdays have often been celebrated with the lighting of beacons.
The last such occasion was in 2012 for the Queen's Diamond Jubilee.
Before the walkabout, the Queen will unveil a plaque for the Queen's Walkway - a four-mile walking trail connecting 63 "points of significance" in Windsor, the palace said.
The walkway was designed by the Outdoor Trust in recognition of the moment on 9 September last year when the Queen became Britain's longest reigning monarch, after more than 63 years on the throne.
The Queen's birthday celebrations also include the Patron's Lunch - a street party on The Mall in London on 12 June for charities of which the Queen is patron.
Tickets for the not-for-profit event were priced at £150 each.