By Jonathan Fildes
Science and technology reporter, BBC News
A congestion-beating project has been launched that could lead to some of the UK's disused railway lines being paved with rubber.
The flexible highways are made of panels of shredded car tyres laid over the existing tracks.
New thoroughfares could be shared by both cars and trams travelling at up to 50mph (80km/h), says Holdfast, the company behind the scheme.
But other users of disused or abandoned railways do not support the plan.
"We would like to see these routes converted into walking and cycling routes," said Gill Harrison, a spokesperson for sustainable transport charity Sustrans.
The charity has converted approximately 1,000 miles (1,600km) of abandoned railway into part of the National Cycle Network.
"More road space does not automatically mean less congestion," she said.
"More roads just get filled up with more cars. We're not saying that cars do not have their place, but ultimately we've all got to think about other ways of getting around."
The rubber roads are being developed by Holdfast Rubber Highway (HRH) and may provide a use for some of the estimated 50m tyres disposed of in the UK each year.
As of 7 July, EU legislation will make it illegal to bury car tyres in landfill sites or burn them, making alternative uses like this more attractive.
Parent company, Holdfast Level Crossings, already makes the rubber decking found at pedestrian and rail crossings.
The company has extended this idea to create cheap interlocking panels that can be laid between the gaps on disused railway lines.
Each mile of track would use 354,000 scrap tyres. Individual panels are made "cold" so there are few emissions in the production process.
A 980ft (300m) demonstration track, funded by the not-for-profit Waste and Resources Action Programme (Wrap), has been built on a branch line leading into a car depot in Corby, Northamptonshire.
Over eight weeks, more than 8,000 cars will drive over the surface to make sure it can stand up to wear and tear.
However, Mr Coates Smith, the managing director of Holdfast, said he was more interested in seeing how quickly the road could be laid.
"It took four men five days to put down 300m of road," he said. "The panels we'd be using [in the future] are three times as long, so you can imagine 900m in five days."
Eventually the jam-busting technology could be used to build a network of roads on the network of "dead" lines, closed by Dr Beeching in the 1960s.
The company is keen to stress that they do not intend to build on disused lines in rural idylls. Instead, they say, the rubber highways will be a cheap alternative to urban bypasses and routes into conurbations.
"We're talking about £1.4m per mile compared with £20m per mile for a new road," said Mr Coates Smith.
Each mile of rubber road uses more than 350,000 scrap tyres
The Highways Agency disputes these costs. They say that £20m buys you a mile of 3-lane motorway, complete with a hard shoulder, rather than just a single-lane rubber highway.
In addition, some people believe that the network of new roads would have limited appeal to most people.
"These tracks are generally disused because they go to places that people don't want to go to," said Roger Ford, industry and technology editor of Modern Railways magazine.
Mr Ford also says that most disused railways have already had their sleepers and rails removed and tend to be overgrown, meaning that installing the road may be more difficult than envisaged.
This is not the first time that rubber has been incorporated into road surfaces. Many roads in Europe and the US have a small portion of rubber crumb mixed with the asphalt to make the road quieter.
However these surfaces have never really taken off in the UK because the damp weather made the road surfaces crack and disintegrate.
Mr Coates Smith believes the new road surface, made almost entirely of rubber, will not suffer the same problems.
Car drivers could soon have an alternative to waiting in traffic jams
"There are no potholes, there's no cracking, no spoiling from frost and it's very quiet," he said.
Maintenance costs are also very low as individual panels can be replaced in 15 minutes, according to Mr Coates Smith.
In addition, as the routes were originally intended for trains, they are also ideally suited for trams.
These carriages would run on the rails, left exposed between the rubber mats, and could carry between 50-100 people, Holdfast believes.
They would share the road with cars. However, the thin lanes would mean that overtaking would be almost impossible.
However, Mr Coates Smith believes that the environmental advantages and the congestion beating nature of the system will make it a success.
He already has a number of companies, transport authorities and local councils, including Fife and Gosport, interested in the technology.
"The response we've had is amazing. My phone has not stopped ringing."