GLASTONBURY, England, June 23 (Reuters) - Britain's Glastonbury Festival fell silent for a minute on Friday in memory of recent terror attacks and the devastating Grenfell Tower fire, before Hacienda Classical eased revellers into the first day of music at the world's biggest greenfield festival.
Peter Hook, the bass player from Manchester bands Joy Division and New Order, led the crowd on the main Pyramid Stage in reflecting on "our hopes and our prayers for life, love and freedom, the things we are here to celebrate".
"Glasto", as it is affectionately known, is headlined later on Friday by Radiohead who 20 years ago performed during one of the wettest years in the festival's history, lifting a sodden crowd with music from their groundbreaking album "OK Computer".
Featuring songs about alienation, capitalism and the impact of modern technology, "OK Computer" sounds oddly prescient in a politically divided and anxious Britain in 2017.
Security has been stepped up at Worthy Farm in Somerset, south-west England, after a suicide bombing at an Ariana Grande concert in Manchester killed 22 last month and three recent attacks in London.
Festival-goers took the extra checks in their stride, more concerned about coping with the hottest June for four decades which slowed activity on site to a crawl.
Temperatures cooled on Friday, the first day of music in which the standout is English band Radiohead in a third headline appearance.
"I am loving the weather. It's perfect Glasto weather," said 23-year-old Laura Cottam in the Hacienda Classical crowd. She said she spent Wednesday looking for shade and cold beer after arriving as soon as the gates opened.
An unlikely marriage between DJs Graeme Park and Mike Pickering and Manchester Camerata Orchestra, Hacienda Classical entertained with floor-fillers from the 80s and 90s, including Ultra Nate's "Free" and New Order's "Blue Monday".
The afternoon line-up on the biggest of more than 12 stages includes 81-year Kris Kristofferson, rock duo Royal Blood, which only formed in 2013, and the English indie band, the xx, before the highly anticipated return of Radiohead.
Fans expected "OK Computer" to feature heavily in the set list on Friday, the same day as a re-release of the album with tracks that did not make the cut 20 years ago, called "OK Computer OKNOTOK 1997 2017".
Chris Glackin from Surrey, who was eight when the album was released, was looking forward to the gig.
"I have grown up my whole life listening to them with my old man, he's never seen them live (...) so I am definitely going to go and see them live," he said. (Reporting by Paul Sandle; Editing by Elisabeth O'Leary and Richard Balmforth)