Dormice, a protected species, have become extinct in some counties
A special rope bridge for dormice to cross a busy road has been built by nature workers on a housing estate.
The "dormouse bridge" has been put up 18 feet above a new relief road at Haywards Heath, West Sussex.
It aims to make sure the protected creatures are not an unwelcome addition to the county's road accident statistics.
Graham Roberts, senior ecologist for West Sussex County Council, was worried about the impact of the road severing a community of the furry mammals.
He suggested the answer could be an aerial walkway similar to ones used by red squirrels on the Isle of Wight.
The developers agreed to pay for five steel reinforced ropes, woven together, which run above the road and are tied to trees on either side of the carriageway.
Lieutenant Colonel Tex Pemberton, a cabinet member for the council, said: "Dormice live almost exclusively in trees and are trained to clutch branches in a vice-like grip from a very early age.
"That means there is very little chance of them plummeting down on passing traffic."
Experts say drivers are unlikely to be distracted - in fact, people will be lucky to see the rope bridge being used.
The dormouse is a protected species
It feeds on berries, nuts, pollen and insects
It is arboreal, which means it tends to live in trees
There are 14 species of nocturnal dormice worldwide
The creatures resemble small squirrels rather than mice
Dormice spend three-quarters of their life asleep and are a strictly nocturnal species.
It is not the first time the council has tried to make the highway network safer for wildlife.
Tunnels for creatures from toads to badgers have been provided in other parts of West Sussex.
Colonel Pemberton said: "This bridge is a novel solution and I am glad the developers took up the suggestion.
"It shows that we take our responsibilities seriously when it comes to the rich and varied wildlife that exists in our county."
The dormouse has become extinct in as many as seven English counties during the last century.
Programmes to re-introduce them are taking place in some parts of the country.
The need for arboreal routes has been pinpointed as vital to make sure that the break-up of woodland areas does not leave dormouse communities isolated and vulnerable.