Planning (Listed Buildings and Conservation Areas) Act 1990 (1990 Chapter 9).
This Act concerns the protection of listed building and the designation and protection of conservation areas. Every local planning authority: (a) shall from time to time determine which parts of their area are areas of special architectural or historic interest the character or appearance of which it is desirable to preserve or enhance, and (b) shall designate those areas as conservation areas. The Secretary of State may from time to time determine any part of a local planning authority's area as a conservation area.