Charles was born to become king, but he had to wait more than 70 years - the longest of any heir apparent.
On the day of his coronation he will become the oldest monarch to be crowned in British history.
From his mother's arms, to his marriage to Diana, to grandchildren of his own - this is his life in pictures.
Charles was born at Buckingham Palace on 14 November 1948, the first child of Princess Elizabeth and Prince Philip - who had married almost exactly a year before.
The future king is seen here cradled by his mother after his christening in the palace's music room, as his father and grandparents look on.
The fair-haired and blue-eyed Charles at 19 weeks old.
He was expected to one day become king, but because of the relatively young age of George VI and Princess Elizabeth when he was born, a wait of many decades seemed inevitable - and so it proved.
Princess Elizabeth, with two-year-old Charles, watches a procession from the wall of Clarence House, during a visit by Dutch royals.
Charles is seen giggling as he sits on a statue at the family's Balmoral estate in Scotland.
Now next in line after his grandfather's death in 1952, Charles pats a horse at Windsor Great Park where Prince Philip was playing polo.
Charles would go on to develop his own love for the sport.
Charles at Cheam School in Berkshire, aged nine.
He was later sent to Prince Philip's former school, Gordonstoun, in Moray, Scotland, an experience he later said he hated.
Charles leaving Buckingham Palace for Windsor Castle in 1965
Charles leaving Buckingham Palace for Windsor Castle in 1965
Playing Macbeth at Gordonstoun School, with the Queen and Prince Philip in the audience
Playing Macbeth at Gordonstoun School, with the Queen and Prince Philip in the audience
The prince batting in 1968 near Ashford in Kent. In slip, is Formula One champion Graham Hill
The prince batting in 1968 near Ashford in Kent. In slip, is Formula One champion Graham Hill
A portrait of Charles for his 18th birthday in 1966
A portrait of Charles for his 18th birthday in 1966
Charles was invested as Prince of Wales on 1 July 1969 at Caernarfon Castle.
To prepare, he spent a term learning Welsh at university in Aberystwyth.
The prince also studied archaeology and anthropology before switching to history at Trinity College in Cambridge.
The Queen gave her son a coronet (a small crown) as she invested him as Prince of Wales.
Charles also received a ring, a sword and robes as he pledged: "I, Charles, Prince of Wales do become your liege man of life and limb and of earthly worship, and faith and truth I will bear unto thee, to live and die against all manner of folks."
Charles parachuted from above Poole Harbour in 1971
Charles parachuted from above Poole Harbour in 1971
Diving under ice at Resolute Bay in Canada in 1975
Diving under ice at Resolute Bay in Canada in 1975
Charles taking aim in his capacity as president of the National Rifle Association in 1978
Charles taking aim in his capacity as president of the National Rifle Association in 1978
A family picture in 1972: Charles next to Prince Edward, his parents, Prince Andrew and Princess Anne
A family picture in 1972: Charles next to Prince Edward, his parents, Prince Andrew and Princess Anne
Charles's military career included training as a jet pilot with the RAF in 1971. He then followed his father, grandfather and both great-grandfathers by joining the navy.
Charles served on missile destroyer HMS Norfolk and two frigates, and commanded minehunter HMS Bronington for nine months.
The prince also qualified as a naval helicopter pilot - a skill both his sons would later learn.
This photo shows him as colonel-in-chief of the Parachute Regiment in 1978.
Charles on his 30th birthday at Balmoral in Aberdeenshire.
This picture shows the then Prince of Wales with his fiancée, Lady Diana Spencer, at Balmoral in 1981.
Charles first met Diana at a grouse hunt when she was 16 at the Spencer family estate in 1977. He was dating her older sister, Lady Sarah McCorquodale, at the time.
Diana and Charles reportedly didn't meet again until they both stayed at a friend's house in Sussex in the summer of 1980.
It was a quick courtship - just a year later they married in a spectacle that captured the world's imagination.
Charles married Diana in front of 3,500 guests at St Paul's Cathedral on 29 July 1981.
An estimated 750 million people watched on TV in more than 70 countries, including more than 28 million in the UK alone.
In the capital, more than 600,000 people lined the streets in celebration.
Charles's 20-year-old bride became the Princess of Wales - and one of the most famous women in the world.
Prince William was born 11 months later and Prince Harry arrived in September 1984.
However, there were problems behind the scenes, with infidelity on both sides. Diana famously said in a BBC interview "there were three of us in this marriage". The couple's separation was announced in 1992 and they divorced in August 1996.
William in his mother's arms outside St Mary's Hospital in London in June 1982
William in his mother's arms outside St Mary's Hospital in London in June 1982
Prince Harry was born two years later, on 15 September 1984
Prince Harry was born two years later, on 15 September 1984
The family on holiday in the Scilly Isles in June 1989
The family on holiday in the Scilly Isles in June 1989
Charles (left) in a tank while visiting British troops in Saudi Arabia in 1990
Charles (left) in a tank while visiting British troops in Saudi Arabia in 1990
Speaking to Rolling Stones star Mick Jagger and Jerry Hall
Speaking to Rolling Stones star Mick Jagger and Jerry Hall
A glum-looking Charles at the state opening of parliament in 1991
A glum-looking Charles at the state opening of parliament in 1991
Prince William with his father in 1994 at the royals' favourite resort of Klosters, Switzerland
Prince William with his father in 1994 at the royals' favourite resort of Klosters, Switzerland
Playing his beloved polo in 1996 in Ansty, Wiltshire
Playing his beloved polo in 1996 in Ansty, Wiltshire
Spice Girl Geri Halliwell famously said she patted the prince's bottom at a Prince's Trust event in 1997
Spice Girl Geri Halliwell famously said she patted the prince's bottom at a Prince's Trust event in 1997
New prime minister Tony Blair with Charles on the Royal Yacht Britannia in 1997
New prime minister Tony Blair with Charles on the Royal Yacht Britannia in 1997
William, 15, and Harry, 12, walk with Prince Charles on the River Dee in 1997
William, 15, and Harry, 12, walk with Prince Charles on the River Dee in 1997
Princess Diana was killed in a car crash in Paris on 31 August 1997.
Her death at 36 led to a huge outpouring of public grief and left her two young sons without a mother.
Pictures of William and Harry walking behind their mother's coffin were watched by an estimated 2.5 billion people around the world.
Charles and his sons look at flowers and messages for Princess Diana
Charles and his sons look at flowers and messages for Princess Diana
Diana's sons alongside Earl Spencer and Charles at the funeral procession. Prince Philip also walked beside them
Diana's sons alongside Earl Spencer and Charles at the funeral procession. Prince Philip also walked beside them
Charles in the foothills of the Himalayas while visiting a Gurkha welfare centre in Nepal in 1998.