Below, Princess Elizabeth talks to her husband Philip, the Duke of Edinburgh,
 at the Royal Horse Show at Windsor, England, on May 12, 1949. She married 
naval officer Philip Mountbatten at Westminster 
Abbey on Nov. 20, 1947. Britain at the time was still economically ravaged by
 the Second World War. 
(Douglas Miller/Keystone/Getty)
The royal couple attend a concert at London's Festival Hall in May 1951. Now 91,
 the Queen is the first British monarch to reach a platinum anniversary. Her 
husband, Philip, is now 96.
(Hulton Archive/Getty)
Then-princess Elizabeth stands with Philip, the Duke of Edinburgh, and their 
children Prince Charles and Princess Anne at the couple's London residence 
at Clarence House in August 1951. Elizabeth became queen in 1952.
Britain Prince Philip
The royal couple wave to supporters from the balcony at Buckingham Palace on June 2, 1953 following her coronation at Westminster Abbey. Philip has spent decades supporting his wife in her role as head of state.
Britain Queen's Platinum Anniversary
(Leslie Priest/AP)
U.S. President Dwight Eisenhower and his wife Mamie had the opportunity 
meet the Queen and her husband at the White House on Oct. 17, 1957. 
Buckingham Palace announced last May that Philip would stop carrying out
 public engagements this fall, and in August he retired from solo official duties.
Britain Prince Philip
Anne, Charles, Prince Andrew and Prince Edward pose for photos with the roya
l couple on the grounds of Windsor Castle on Dec. 19, 1965.
Britain Queen’s Platinum Anniversary
Charles, Edward at age 8, Andrew at age 12 and Anne at age 22 gather with their 
parents at Buckingham Palace to mark the royal couple's silver wedding anniversary 
on Nov. 20, 1972.
Britain Queen’s Platinum Anniversary
Elizabeth and Philip walk on the grounds of Sandringham House on Feb. 4, 1982
 to commemorate the 30th anniversary of the Queen's accession to the throne. 
Sandringham has served as a royal retreat for generations.
Travel Royal Retreat
Elizabeth and Philip made numerous trips to Canada as a couple. Here they are
driven in an open car after attending ceremonies at Victoria Park in Moncton, N.B., on Sept. 24, 1984.
(Fred Chartrand/Canadian Press)
U.S. President George Bush and his wife Barbara stand with the royal couple 
on Nov. 30, 1993 after Bush had been awarded an honorary Knight Grand
 Cross of the Order of the Bath by the Queen at a private lunch in London.
(Johnny Eggitt/AFP/Getty)
The royal couple had been through difficult times together, including the
 death of Princess Diana. Here, Elizabeth and Philip look at tributes 
left in memory of the Princess of Wales at Buckingham Palace on Sept. 5, 1997. 
This was ahead of funeral services for Diana, who died following a car crash in
 Paris days before. 
(Santiago Lyon/AP)
Prince Harry, left, appears with his uncles Andrew and Edward, far right, and
 the Queen and Duke of Edinburgh to watch the flypast over The Mall of British
 and U.S. Second World War aircraft from the Buckingham Palace balcony on
 National Commemoration Day on July 10, 2005 in London. Poppies were 
dropped from the Lancaster Bomber of the Battle Of Britain Memorial Flightas 
part of the flypast. 
(Daniel Berehulak/Getty)
The Queen raises her hand during a downpour as she stands with Philip and
 Charles, Prince of Wales, on the balcony of Buckingham Palace after the
 Trooping the Colour ceremony on June 16, 2007 in London. Each year the
 official birthday of the Queen is commemorated with a military parade and 
march-past of fully trained, operational troops from the Household Division.  
(Peter Macdiarmid/Getty)
Prime Minister Stephen Harper, the Queen and her husband arrive on stage for
the Canada Day celebrations on Parliament Hill on July 1, 2010 in Ottawa. 
The Queen and Duke of Edinburgh took part in an eight-day tour of Canada in
 2010 starting in Halifax and finishing in Toronto. The trip was to celebrate 
the centenary of the Canadian Navy and to mark Canada Day. The royal
 couple then headed to New York where the Queen addressed the UN and 
visited Ground Zero.
(Chris Jackson/Getty)
The royal couple wave farewell to Australia at the Perth International Airport
 on Oct. 29, 2011. Thousands turned out for the Queen and Prince Philip's 
farewell in Perth where she thanked well-wishers at the end of the 10-day 
visit, her 16th tour of Australia. 
(Lincoln Baker/Getty)
Elizabeth and Philip sit in the House of Lords as she waits to read the Queen's 
Speech to legislators in London on May 9, 2012. 
Britain Prince Philip
(Alastair Grant/AP)
The royal couple are shown the Olympic flame at Windsor Castle on Day 53
 of the London 2012 Olympic Torch Relay on July 10, 2012 in Windsor. The 
Olympic Flame went on a 70-day relay involving 8,000 torchbearers and
 covered 12,875 kilometres.
(Steve Parsons/WPA/Getty)
Philip, Elizabeth and Prince Charles attend the Braemar Gathering, or highland
 games, at The Princess Royal and Duke of Fife Memorial Park on Sept. 1, 2012 
in Braemar, Scotland. The event is known worldwide. Each year, thousands of
 visitors descend on this small Scottish village on the first Saturday in September
 to watch one of the more colourful Scottish traditions. The gathering has a long 
history and in its modern form it stretches back nearly 200 years.
(Jeff J. Mitchell/Getty)
The royal couple react as they bid farewell to Irish President Michael 
D. Higgins and his wife Sabina at the end of their official visit to Win
dsor Castle on April 11, 2014 in Windsor. Higgins made the first state
 visit by a president of the republic since it gained independence 
from neighbouring Britain. The visit came three years after the Queen
 made a groundbreaking trip to the republic, which helped to heal deep
-rooted unease and put British-Irish relations on a new footing. 
(Leon Neal-WPA/Getty)
The royal couple arrive to officially reopen Canada House following an extensiv
e program of restoration and refurbishment, in Trafalgar Square in London on 
Feb. 19, 2015. Canada House is the official
 home to the Canadian High Commission in the United Kingdom. The building 
was first opened in 1925 by King George V. 
APTOPIX Britain Canada Royals
(Kirsty Wigglesworth/AP)
Members of the royal family: Camilla, the Duchess of Cornwall; Prince Charles;
 Princess Eugenie; the Queen; Timothy Laurence; Princess Beatrice; Philip; Kate,
 the Duchess of Cambridge; Princess Charlotte; Prince George and Prince 
William watch a fly-past as they appear on the balcony of Buckingham Palace,
 after attending the annual Trooping the Colour ceremony in London on 
June 17, 2017.
Britain Queen's Platinum Anniversary
(Kirsty Wigglesworth/AP)
With files from Associated Press, The Canadian Press, EPA and Getty