The Duke and Duchess of Cambridge have introduced their daughter to the world, as they left hospital to take her home to Kensington Palace.The princess, whose name has yet to be announced, slept in her mother's arms during her first public appearance outside St Mary's Hospital, in London.
The princess - who is fourth in line to the throne - was delivered at 08:34 BST on Saturday after a short labor.
The Duke of Cambridge was present for the birth of the 8lbs 3oz (3.7kg) baby.
The couple emerged from the hospital to crowds of well-wishers and the world's media. They stood on the steps briefly before heading back into the hospital to put the princess in a car seat. Prince William then drove them to Kensington Palace.
They did not speak to the media.
The duchess had been in hospital for just over 12 hours before leaving.
The baby was born less than three hours after the couple arrived at the Lindo Wing, at St Mary's Hospital.
Outside the Lindo Wing: BBC royal correspondent Daniela Relph
It all happened rather quickly in the end.
Within 12 hours of arriving at the hospital in the early stages of labour, the duchess had left St Mary's with her new baby in her arms and her husband at her side.
That moment on the Lindo Wing steps - the royal couple and their daughter - will be one of the defining images of the year.
Wrapped in a white shawl for her first photocall, the baby princess appeared to sleep all the way through it.
There'll be no name announced this evening. That may take a few days.
The Cambridges are now back at Kensington Palace for their first night together as a family of four
The family will stay for a few days at Kensington Palace before decamping to their country home, Anmer Hall on the Sandringham estate in Norfolk.
The duchess had been admitted to the private Lindo Wing at St Mary's Hospital in Paddington, west London, at 06:00 BST.
The birth announcement came about 11:00 BST, and the couple left the hospital with their daughter shortly after 18:00 BST.
While the birth was announced on Twitter, there was still room for tradition with an easel announcing the birth placed in the courtyard of Buckingham Palace. The birth was also proclaimed by a town crier who was not on official duty but certainly entertained the crowds outside the hospital.