US-style "megafarms" are sweeping across the UK, a major Bureau investigation has revealed, a shift that is changing the face of British agriculture.

The increase in megafarms – which can house more than a million chickens, 20,000 pigs or 2,000 cattle apiece – is part of a 26% rise in intensive livestock farming over the last six years. Read the full investigation here.

We were invited to see firsthand what this kind of farming looks like, by Herefordshire farmer Richard Williams. From two sites he produces more than two million chickens a year for the giant food company Cargill, which supplies Tesco.

All photos by Rob Stothard

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In a valley in rural Herefordshire, near the village of Kington, an orchard leads down to a tarmac road. Through a gap in the trees, four industrial sheds can be seen, giant green cylinders rising up behind them.



If you stand still you can hear a murmuring of chickens. From the top of the hill there is no odour, but nearer to the sheds, the sweetish, sickly smell is overpowering.