Wild bison have been released into the Kent countryside in a £1.2 million project to “re-wild” the countryside.
Bison have been extinct in Britain for more than 6,500 years.
Experts believe bringing it back will help revitalise ancient woodlands and create an “explosion of biodiversity”.
A male and three females have been set free in a wildlife area near Canterbury.
They are European Bison – a close relative of the species that once roamed the UK – and can weigh up to one tonne.
They create muddy ponds, push down trees and disturb the soil – all helping plants and other animals to survive.
Paul Whitfield, director-general of the Wildwood Trust, which is leading the project with the Kent Wildlife Trust, said:
“They will create an explosion of biodiversity and build habitat resilience, locking in carbon to help reduce temperature rise.
“This will act as a huge catalyst for change.”
Evan Bowen-Jones, chief executive of Kent Wildlife Trust, added:
“We need to revolutionise the way we restore natural landscapes – relying less on human intervention and more on natural engineers such as bison, boar and beaver.”