Cities continue to get bigger and bigger. People want to live in the leafy suburbs. Modern supermarket chains like Asda want to set up new stores on the edge of town. Here land is cheaper, and there is space for the large car parks. Ring roads and by-passes are build around cities. All this means that more and more countryside and farmland is lost.

One solution is to declare a "green-belt" around urban areas, where development is not allowed. This has not always been successful as new factories bring jobs and housing is often in great demand. Developments have also been "leap-frogging" the green belt and been built further away from the city.