Sir David Attenborough made a surprise appearance at Glastonbury and hailed its ban on single-use plastic bottles.
It is thought he was the oldest person to ever take to the main stage at the music festival.
The broadcaster, 93, thanked organisers for ditching the sale of plastic at the event for the first time in its 49-year history.
He said he was proud his Blue Planet II documentary series had highlighted the dangers of plastic.
After being greeted by a gigantic roar as he arrived on the Pyramid Stage yesterday, he told the huge crowd: “There was one sequence that everyone seems to remember, that showed what plastic has done to the creatures in the ocean.
"It has an extraordinary effect.
“Now this great festival has gone plastic free. That is more than a million bottles of water that have not been drunk by you in plastic. Thank you. Thank you...
“There are seven great continents on which we human beings live. Each has its own marvellous creatures... its own glory... its own problems.”
Many in the crowd were moved by his words.
One of the 175,000 festival goers, Adrian Lake, said Sir David had brought a tear to his eye, adding: “He is the voice of the world’s creatures and we need to join him in being that voice also.”
Festival co-organiser Emily Eavis said: “People are really starting to understand how important it is to treat the land with respect, and to stop living a disposable lifestyle.”
Sir David, who spoke before Kylie Minogue’s slot on the stage, was there to launch his next major BBC series – Seven Worlds, One Planet – likely to start this autumn.
