Why Accession Day — February 6 — Is One of the Saddest Days for Queen Elizabeth

As Queen Elizabeth remarked on the day she passed Queen Victoria’s record reign in September 2015, a long life can bring with it “many milestones.”

And now the 93-year-old monarch is set for yet another big milestone: 68 years on the throne, as February 6 marks the death of her father, King George VI, and also the day she became Queen.

Known as Accession Day, the Queen normally spends it in quiet, somber reflection at Sandringham House, as it marks the death of her beloved father as much as the day that her public life changed forever. Around the time, she often takes part in a low-key engagement close to her estate in Norfolk.

Soon after the date passes, she’ll head south to London and Windsor Castle for a fuller set of public and behind-closed-doors work, such as audiences with diplomats and meetings with the U.K. Prime Minister.

“By the sudden death of my dear father I am called to assume the duties and responsibilities of sovereignty,” she said in her speech to the accession council.

“My heart is too full for me to say more to you today than I shall always work as my father did throughout his reign, to advance the happiness and prosperity of my peoples, spread as they are all the world over.”

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In June 1953, several months after her father’s death, Elizabeth was crowned at Westminster Abbey.

The next milestone? Her 94th birthday on April 21.