How scientists will use urine collected from festivalgoers in national park project

The native trees will be grown on the edge of Bannau Brycheiniog, also known as the Brecon Beacons, in Wales - (PA)

Scientists will use fertiliser made from urine collected from festivalgoers to grow up to 4,500 trees at a national park.

Bristol-based start-up NPK Recovery created the fertiliser using urine collected from a block of toilets used by 700 revellers at Boomtown Festival in Hampshire in July last year.