Market towns like Tavistock were highlighted as 'successes'

More than 100 towns were given a 'health check' by the Campaign to Protect Rural England (CPRE).

The report published on Wednesday calls on planners to make careful decisions about developments in market towns.

It found serious traffic congestion and over-stretched services in many towns, caused by new building.

More people are being encouraged to commute to work threatening to turn towns into dormitories.

The car increasingly dominates travel patterns often to the detriment of pedestrians Tom Oliver, CPRE's head of rural policy

And it shows the life is being sucked from high streets by shopping developments built outside towns or in bigger neighbouring towns.

Tom Oliver, CPRE's head of rural policy, said: "Many of our market towns do not have the capacity to cope with major new development.

"Towns are also suffering badly from development which damages their individual character, is insensitively sited, or which threatens local businesses.

"Traffic and congestion within towns is rising and the car increasingly dominates travel patterns often to the detriment of pedestrians.

"Local employment is suffering and local businesses are often undermined by the increasing presence of large national retailers."

Successful Market Towns Tavistock (Devon) Easingwold (North Yorkshire) Frome (Somerset) Saffron Walden (Essex) Maldon (Essex Market Bosworth (Leicestershire) Skipton (North Yorkshire) Wimborne (Dorset) Longridge (Lancashire) Ludlow (Shropshire) Sheringham (Norfolk) Alnwick (Northumberland) Sleaford (Lincolnshire) Holmfirth (West Yorkshire) Oakham (Rutland) Cirencester (Gloucestershire) Faversham (Kent) Barnard Castle (Durham) Sandwich (Kent) Guisborough (Cleveland)

Scarcity of local materials or styles in designs for new buildings and the lack of local produce in shops is also a danger to a market town's distinctiveness.

This erosion of character and attractiveness matters according to the conservation group because distinctive market towns are part of the lifeblood of the English countryside.

However it lists a top 20 of successful towns including Tavistock, in Devon, Sandwich, in Kent, Frome, in Somerset, Market Bosworth, in Leicestershire, Maldon, in Essex , Easingwold, in North Yorkshire and Wimborne, in Dorset.

It says each town builds on a good setting and well-conserved heritage, aswell as demonstrating community spirit and civic pride, local markets, events and festivals and good planning.

CPRE is urging planners to act to retain and develop market towns' character.

It says planning policies must keep economic and retail developments inside market towns and encourage the use of already developed land to save the countryside for those living in the towns and to attract visitors.

The 'health check' survey was carried out between March and October last year.