Westminster Abbey´s bells will peal, a flotilla will sail down the River Thames and a gun salute will ring out on Wednesday as Queen Elizabeth II becomes the longest-serving monarch in British history.
The queen herself is set to inaugurate a railway line in Scotland and host a private dinner at Balmoral Castle to mark the day she overtakes her great-great grandmother queen Victoria´s record.
It is not known where exactly she will be at 1630 GMT, the best estimate from royal officials for the time at which the monarch, who has become synonymous with Britain itself, reaches the landmark.
But at that moment, she will have served 23,226 days, 16 hours and roughly 30 minutes on the throne — over 63 years.
Prime Minister David Cameron is expected to lead tributes in parliament to a figure best known internationally for her stoicism in the face of a slew of royal scandals, as well as her colourful outfits.
“Her Majesty has been a rock of stability in a world of constant change,” Cameron said in a statement.
“It is only right that today we should celebrate her extraordinary record, as well as the grace and dignity with which she serves our country.”
The queen may deliver a speech for the occasion, according to media reports, although a royal source has said she wants to keep the occasion low-key because of the memories it evokes.
“While she acknowledges it as an historic moment, it´s also for her not a moment she would personally celebrate, which is why she has been keen to convey business as usual and no fuss,” the source explained.
Elizabeth became queen upon the death of her father George VI, Britain´s king during World War II, whose youthful stutter inspired the Oscar-winning film “The King´s Speech”.
The calculation of her time on the throne is based on when he passed away, which is estimated at around 1:00 am on February 6, 1952 — an hour after he was seen for the last time at his bedroom window at Sandringham House in eastern England.
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