Former Blue Peter host John Noakes has died aged 83, a family friend has announced.
His family said he died peacefully in his sleep on Sunday morning and that they hoped Noakes would be remembered for "his many escapades with his faithful companion Shep" during his time on the TV show.
He had been suffering from Alzheimer's.
Family friend Wendy Downes said in a statement: "John Noakes died peacefully on Sunday morning, May 28.
"He had endured and suffered from Alzheimer's over recent years and whilst he will be greatly missed by his wife, family and many friends, his release from continuing ill health must be counted as a blessing.
"His many escapades with his faithful companion Shep, during his time with Blue Peter, will live on in many peoples memories and that is how his family would like him remembered."
Noakes was Blue Peter's longest-serving presenter.
The Yorkshire-born star worked on the children's show for 12-and-a-half years in the 1960s and 1970s, when he developed a reputation as the show's action man.
He was also known for his partnership with canine stars of the programme, Patch, the first Blue Peter dog Petra's puppy, and the border collie Shep, who inspired Noakes's catchphrase: "Get down, Shep!"
In 2015, Noakes was found near his home in Majorca after going missing for more than eight hours.
He was discovered in a storm drain, after being spotted by a police helicopter, not far from his home and taken to hospital in the city of Palma.
Police in Andratx on the south west of the Mediterranean island were alerted to his disappearance as temperatures reached almost 36C (96.8F).
Noakes landed the Blue Peter job after notching up small TV parts in series like Redcap and Mogul, when editor Biddy Baxter decided to have a third presenter on the show to join Christopher Trace and Valerie Singleton.
His feats while included ascending Nelson's Column without a safety harness using just a rickety wooden ladder, a sound problem meant he had to repeat the climb, a bruising encounter with a bobsleigh and a record-breaking skydive.
As well as Blue Peter, he made 1970s travelogue spin-off Go With Noakes, where he travelled around the UK with Shep alongside him.