Factbox-Four days of celebration mark Queen Elizabeth's Platinum Jubilee

LONDON (Reuters) - Britain began four days of celebrations on Thursday to mark Queen Elizabeth's seven decades on the throne.

The 96-year-old Elizabeth, Britain's longest-reigning and currently the world's oldest monarch, became queen on Feb. 6, 1952, on the death of her father King George VI.

There will be events held over two public holidays and the weekend, with the queen planning to attend a number of them.

Here are details of the celebrations:

JUNE 2

The Queen's Birthday Parade, known as "Trooping the Colour" and which has been held for more than 260 years, will be held in central London with more than 1,200 soldiers taking part along with military bands.

The queen has attended every such parade bar one since 1955, with scaled-down ceremonies taking place in the last two years because of coronavirus restrictions. Due to her mobility issues, for the first time she will take the salute from soldiers and officers from the balcony of Buckingham Palace.

There will be gun salutes at midday and a fly-past by modern and historic Royal Air Force planes. After the parade, the queen will be joined by working members of the royal family on the palace balcony to salute the crowds.

In the evening, beacons will be lit in more than 2,000 towns, villages and cities across Britain and in the capital cities of Commonwealth countries. The queen will lead the lighting of the Principal Platinum Jubilee Beacon at her Windsor Castle home.

JUNE 3

A national service of thanksgiving will be held at London's St Paul's Cathedral, and its 'Great Paul' bell - the largest in the country and dating back to 1882 - will be rung for the first time at a royal occasion since being restored last year after a mechanism broke in the 1970s.

After the service, a reception will be held at London's Guildhall hosted by the Lord Mayor of the City of London.

JUNE 4

Members of the royal family will attend Epsom racecourse as it stages the 243rd running of "The Derby" horse race.

The queen, whose love of horse racing is well known and who is an owner and breeder of many horses, has been a regular attendee at the race in previous years.

In the evening, a "Platinum Party at the Palace" concert will be staged at the front of Buckingham Palace. Those appearing include American R&B singer Alicia Keys, U.S. singer Diana Ross and Lin-Manuel Miranda, creator of hit musical "Hamilton".

JUNE 5

"Big Jubilee Lunches" and an estimated 16,000 street parties will be held across the country, with some 600 also being staged across the globe, including in Canada, Brazil, New Zealand, Japan and South Africa.

In the afternoon, a pageant will be held in central London with the Gold State Coach at its head that Elizabeth used on her coronation day in 1953. It has not been seen on the streets of the capital for 20 years.

Organisers have said singer Ed Sheeran and more than 100 well-known figures from British cultural life will join some 10,000 performers and members of the armed forces for the parade, which will trace a route similar to that taken by the queen on the day of her coronation.

(Reporting by Michael Holden; Editing by Gareth Jones and Janet Lawrence)