The CPRE said finding tranquillity in the countryside matters deeply to people because it is considered to contribute to mental and physical health and to quality of life.

To make the map, researchers from Northumbria and Newcastle Universities consulted more than 1,300 countryside users and visitors across England on their perceptions on what did and did not make them feel tranquil.

Working from these responses, the team employed computer-based techniques and geographical databases to show how likely every part of England is to make a visitor feel tranquil.

The spectrum of colours ranges from deep red - within towns and cities and along major roads - shading through orange and yellow to a rich green in the most unspoilt areas of deep countryside.

Mr Spiers said: "We know that tranquil areas are shrinking and fragmenting because of the remorseless growth in road traffic and flying and the gradual spread of towns, cities and infrastructure into the countryside.

"Our new mapping method gives us a practical, reliable method of showing where tranquil places can still be found.

"This is the start of our campaign to persuade national and local government, planners, developers, business and public bodies to start using it in order to safeguard tranquil areas for the future and even enhance them."

The CPRE claims that unless government policies are introduced to protect tranquillity, there will be further shrinkage and fragmentation of tranquil areas.

It said tranquillity is affected through new buildings and infrastructure, growing traffic and expanding roads, more flights, flight paths and runways and increased light pollution.