Prince Philip has left King Edward VII’s Hospital in London after his month-long stay.
The Duke of Edinburgh has returned to Windsor Castle after leaving hospital on Tuesday 16 March.
He was admitted to hospital on 16 February as a precaution based on the advice of his doctor.
Philip was then transferred to St Bart’s to be treated for an infection on Monday 1 March after spending almost two weeks at King Edward VII’s.
So, why was Prince Philip admitted to hospital, how is his health and how old is he?
Here is everything you need to know.
Why was Prince Philip in hospital?
Prince Philip was originally admitted to hospital after feeling ill for a short period before his doctor was called.
He was not admitted in an emergency, and instead travelled to King Edward VII Hospital by car.
The duke also walked into the hospital unaided, a palace source said at the time.
The exact reason for the admission has not been made public, but his condition was not related to coronavirus.
Both Philip and the Queen received their Covid-19 vaccines from a household doctor at Windsor Castle in January.
In the original statement released on Tuesday 16 February, Buckingham Palace said: “His Royal Highness the Duke of Edinburgh was admitted to King Edward VII’s Hospital in London on Tuesday evening.
“The duke’s admission is a precautionary measure, on the advice of His Royal Highness’s doctor, after feeling unwell.
“The duke is expected to remain in hospital for a few days of observation and rest.”
Prince Philip stayed at King Edward VII Hospital for 13 nights.
He was then treated for an infection after being transferred to St Bartholomew's Hospital on Monday 1 March for continued observation and tests on his heart condition.
The duke was transferred about three miles to the new hospital in the City of London.
Buckingham Palace said the procedure for his heart condition took place on Wednesday 3 March.
He was then transferred back to the original hospital where he remained for a number of days.
The Duke of Edinburgh has now been discharged from hospital and back to Windsor Castle "following treatment for an infection and a successful procedure for a pre-existing condition".
How is the duke’s health?
Prince Philip is said to be in good spirits after his hospital stay.
He left through a side entrance of King Edward VII's hospital in a wheelchair before he was helped into a waiting car.
In a statement on Tuesday 16 March, Buckingham Palace said: “His Royal Highness wishes to thank all the medical staff who looked after him... and everyone who has sent their good wishes.”
Prince Charles, speaking during a visit with the Duchess of Cornwall to a pop-up vaccination centre in London, told reporters it was “very good news” and he was “thrilled” that the duke had left hospital.
He was the first member of the royal family to visit Philip in hospital on Saturday 20 February.
He made the 100-mile trip from his home in Gloucestershire and stayed for around 30 minutes.
The hospital’s website states that visits under the current lockdown rules are permitted in “exceptional circumstances”.
Two days later, the duke’s grandson Prince William told reporters that he was doing “OK” and that doctors were “keeping an eye” on him.
The Queen stayed at Windsor Castle and continued to work after Prince Philip was admitted to hospital.
Does Prince Philip have other health issues?
It is not the first time Prince Philip has been admitted to hospital.
In December 2019, he was sent to King Edward VII Hospital as a "precautionary measure" to receive treatment for a "pre-existing condition".
He was then discharged after four nights and was driven to Sandringham where he spent Christmas with the Queen.
And in 2011, Philip was taken to hospital by helicopter from Sandringham after suffering chest pains as the royal family was preparing for Christmas.
He was treated for a blocked coronary artery at Papworth Hospital in Cambridgeshire.
How old is Prince Philip?
Prince Philip, also known as the Duke of Edinburgh, was born on 10 June 1921 in Corfu, Greece.
The 99-year-old will hit a significant milestone this year when he turns 100 in the summer.
His father was Prince Andrew of Greece and Denmark and his mother was Princess Alice of Battenberg.
However, the family were exiled from the country when Philip was a baby.
Philip's uncle took the Greek crown as Constantine I, but in 1922 he was forced from the throne by a military uprising.
The family left the country on a British boat and travelled to France.
Where did Prince Philip grow up?
Prince Philip was then educated in France, Germany and the UK before joining the Navy in 1939, when he was 18.
He graduated from the Royal Naval College in Dartmouth before serving in World War II.
Philip ultimately reached the rank of commander in 1952.
He also holds a host of honorary ranks, including Captain General of the Royal Marines, and in 2011 he was appointed Lord High Admiral of the UK.
When did he marry Queen Elizabeth?
Prince Philip married Queen Elizabeth II in 1947 after a five-month engagement.
The Queen was 21-years-old when she married, while Philip was 26.
The pair first met in 1934 and exchanged letters for years before seeking permission from King George VI to become engaged.
They have four children - Prince Charles, Princess Anne, Prince Andrew and Prince Edward - as well as eight grandchildren and eight great-grandchildren, with one more on the way.
As part of the royal family, Philip has been the patron of many organisations and has often attended events with the Queen.
The Duke of Edinburgh formally retired in 2017, marking the moment with a parade of Royal Marine commandos at Buckingham Palace.
In November 2020, the Queen and Prince Philip marked their 73rd wedding anniversary.
They released a photo of themselves opening a card made for them by the Duke and Duchess of Cambridge’s children.
Why is Prince Philip not king?
Prince Philip didn’t become a king when he married the Queen due to a parliamentary law.
Over the course of British history, the husband of a queen born into the line of succession has not become a king.
It was the same case for the husbands of Queen Anne and Queen Victoria.
The spouse of a ruling king or queen is instead known as a consort.
After the Queen ascended the throne in 1952, Prince Philip was only known as the Duke of Edinburgh, which was given to him by King George VI.
And in 1957, the Queen made the decision to make Philip a prince of the UK, in addition to his dukedom.