Gun salutes will be held today to mark the 62nd anniversary of the Queen's accession to the throne.
They will include a 41-gun salute by the King's Troop Royal Horse Artillery in London's Hyde Park at midday, and a 62-gun salute by the Honourable Artillery Company from Gun Wharf at the Tower of London at 1pm.
The day will be a sombre one for the Queen as it is the moment she became monarch on the death of her father King George VI.
He died on February 6 1952 after suffering from lung cancer.
The Queen was thousands of miles away at the time in Kenya, watching big game in the Treetops Hotel with the Duke of Edinburgh, unaware of the momentous duty that had fallen upon her shoulders.
Philip broke the sad news to his wife and the royal couple returned to Britain.
The Queen is preparing for a busy time over the next few months. It was announced this week that the Queen and the Duke of Edinburgh are to travel to Normandy to attend events commemorating the 70th anniversary of the D-Day landings as p art of a three-day state visit to France in June, and in April they will make a one-day visit to Rome, and will have an audience with Pope Francis at the Vatican.
The trip to Italy was originally scheduled for last year but was postponed because the Queen was unwell.
The Queen is expected to spend today privately.