Frankel, the world's best racehorse, has left Newmarket's Warren Place stables, ending a three-year link with trainer Sir Henry Cecil.
The four-year-old has travelled to his birthplace, Banstead Manor in Cheveley, where he will be put to stud next year.
Frankel was retired unbeaten last month after winning an unprecedented 14 out of 14 races.
"I am pretty certain that there has never been a better or more talented thoroughbred," said Cecil.
"There is no doubt Frankel has been a brilliant racehorse. He had the speed to be a champion sprinter and then, once he grew up and settled, he got a distance with a turn of foot that makes champions.
"Today is a sad day in some ways for us as he has given us so much pleasure over the last three years.
"But I want to thank Frankel for so much - for being such a very special part of my training career. Thank you, Frankel."
The £100m valued colt, son of three-time Group One winner Galileo, bowed out with a thrilling victory in the Champion Stakes at Ascot last month.
His stock will be in high demand at the Banstead Manor Stud, where he will be managed by owner Prince Khalid Abdullah's Juddmonte team.
The unbeaten Australian mare Black Caviar and Cecil's former charge Midday have been touted as potential partners.
Juddmonte general manager Philip Mitchell said: "In the foaling unit on February 11th 2008 at 11.40pm, little did we realise that we were witnessing the birth of a phenomenal racehorse.
"The rest, as they say, is history and it is now extremely exciting that Frankel will be returning to the stallion unit at Banstead, some 500 yards from where he was born."