Ancient woodland is being dug up and moved 200 metres to make way for a new dual carriageway in Nottinghamshire.
The 1.2 hectare Roehoe Wood, near Widmerpool, is thought to have been woodland for more than 500 years.
The route of the new A46 passes through the wood, meaning soil and trees in its path need to be relocated.
The road is being upgraded between Newark and Widmerpool in a bid to relieve congestion, improve safety and boost the local economy.
David Griffiths, senior environmental adviser for the Highways Agency, said: "While the trees themselves are not ancient, the plants found growing amongst the trees indicate that the site is likely to have been continuously wooded since the primeval forest established itself across the whole of Britain after the last ice age.
"The soil is particularly rich and fertile and is home to lots of fungi that encourages growth of new trees."
An environmental team carried out surveys to identify which trees and shrubs were suitable for moving.
They will be coppiced with excess wood removed and the stumps, roots and topsoil moved to the new site.
Dead wood will also be moved to provide habitats for insects, spiders and small mammals.
Mr Griffiths said: "We have carried out protected species surveys for bats and newts and have provided new habitats for them in the form of bat boxes and ponds.
"The wildlife won't stick around during the move but we certainly anticipate they will colonise the new woodlands.
"We will keep a careful eye on the new sites to see how well they establish and additional planting will be carried out to fill any gaps where trees do not survive the move."
Trees being moved include oak, ash, hawthorn, blackthorn, hazel and willow.
The Agency also plans to add new ponds and hedgerows along the route.
The new road will provide eight improved junctions, a better roundabout at Farndon and bypasses for East Stoke and Farndon. The project is due to be completed in summer 2012.