Out of town retail developments need not be bad for the environment. Out of town centres are often built on land that would otherwise be derelict (e.g. Sheffield's Meadowhall Mall or Bluewater in Kent) and so, if anything, improve the quality of the area. Building modern retail outlets large enough to be economic in urban centres would also involve a great deal of destruction and the sacrifice of historic buildings and local character. Local pollution can be greatly reduced by using modern energy-saving designs which are not possible in city-centre locations, and by providing bus and light-rail services from nearby population centres.