Diamond Jubilee: Queen's Accession To Throne Mark's Death Of Beloved 'Papa' George VI
For the Queen, February 6 denotes the very beginning of her reign and a great sadness at the death of her beloved "Papa".
Although he faced several years of worsening health including lung cancer, George VI died unexpectedly in his sleep at Sandringham in 1952.
The Queen normally spends the joint anniversary of her accession to the throne and her father's death in private, staying out of the public eye.
Close to her father as a child, Elizabeth was said to be similar to him in character and, according to royal author Sarah Bradford, they shared a "dedicated professionalism".
February 6 officially signifies the monarch's Diamond Jubilee - 60 years to the day that she became Sovereign.
When the king died, Princess Elizabeth was thousands of miles away 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.
They were resting after returning to the Sagana Lodge which had been given to them as a wedding present by the people of Kenya when the message was given to Philip by his equerry and friend Mike Parker.
The Duke looked as if half the world had been dropped on him, his close aide once said.
Philip broke the sad news to his wife while they were alone. Princess Elizabeth, now Queen, was ready to fulfil her duty.
Lord Charteris, her then-private secretary, remembered seeing her seated at her desk in the Lodge appearing "very composed, absolute master of her fate".
Asked what name she wished to use as Queen, she is said to have replied simply: "My own name, of course."
The remainder of the Commonwealth tour was immediately cancelled and swift arrangements were made for their return home.
After a long plane journey, the young Queen - a slim, pale figure, dressed in mourning black - made her way down the steps, ahead of the Duke of Edinburgh, and set foot on British soil on February 7 for the first time as Sovereign.
Prime Minister Winston Churchill was the first to greet her on the runway at London Airport.
Elizabeth had left as a Princess and returned as a Queen at the age of just 25.
Crowds gathered in the streets to solemnly watch the new monarch be driven past in a black Rolls-Royce.
On February 8, Elizabeth II was formally proclaimed Queen at a meeting of the Accession Council in St James's Palace to which all members of the Privy Council were summoned.
The House of Lords, the Lord Mayor, aldermen and other leading citizens of the City of London, and the high commissioners in London of member nations of the Commonwealth were also invited to attend.
The Queen's father was laid to rest in the vault of his ancestors at St George's Chapel, Windsor, on February 15.
In recognition of her 50 years on the throne in 2002, the Queen spent the Golden Jubilee accession day opening a cancer unit in memory of her father.