Single-use plastic bottles are to be banned from sale at Glastonbury.
An announcement on the festival's website said the containers would not be supplied backstage, nor to catering or production staff.
Festivalgoers have also been urged to carry "as little single-use plastic as possible".
Organiser Emily Eavis encouraged ticket-holders to bring reusable bottles and said "hundreds of free water taps" would be available.
A Glastonbury spokesman said more than one million plastic bottles were sold at 2017's event.
Ms Eavis said it was "paramount for our planet" to reduce plastic consumption.
"I'm thrilled that, together, we'll be able to prevent over a million single-use plastic bottles from being used at this year's festival."
Acts confirmed for this year's event include Janelle Monae, Stormzy and Kylie Minogue.
The festival, held in Pilton, Somerset, since 1970, had a "fallow year" in 2018 to allow the ground to recover.