Fifty years ago, on 21 August 1976, the Rolling Stones headlined a huge open-air festival at Knebworth House in England, drawing around 100,000 fans in what was billed at the time as one of Britain's most significant rock events. The show mattered because it came after a turbulent year for the band: it was staged just weeks after guitarist Keith Richards suffered the loss of his ten-day-old son Tara to SIDS, and amid lurid press coverage accusing the band's entourage of unwittingly smuggling drugs during a gruelling nine-country European tour.

The Knebworth bill featured support from 10cc, Lynyrd Skynyrd, Todd Rundgren and Hot Tuna, and contemporary reports framed it as a possible swansong, with Mick Jagger, then 33, quoted as saying he'd hate to still be singing "Satisfaction" at 40. Press speculation that the Stones might retire after the gig was widespread at the time, though largely dismissed as ticket-selling hype whipped up by promoters; the band, of course, continued performing for decades afterwards.