Local authorities (including National Park Authorities) have the power to designate conservation areas in any area of 'special architectural or historic interest' whose character or appearance is worth protecting or enhancing. This 'specialness' is judged against local and regional criteria, rather than national importance as is the case with listing. The special character of these areas does not come from the quality of their buildings alone. The historic layout of roads, paths and boundaries; characteristic building and paving materials; a particular 'mix' of building uses; public and private spaces, such as gardens, parks and greens; and trees and street furniture, which contribute to particular views - all these and more make up the familiar local scene. Conservation areas give broader protection than listing individual buildings: all the features, listed or otherwise, within the area, are recognised as part of its character. Trees make an important contribution to the character of the local environment. Anyone proposing to cut down, top or lop a tree in a conservation area, whether or not it is covered by a tree preservation order, has to give notice to the local authority. The authority can then consider the contribution the tree makes to the character of the area and if necessary make a tree preservation order to protect it. The first conservation areas were created in 1967, and there are now over 8000 conservation areas in England. This dataset is used as a planning constraint.