The dataset contains the original site boundaries for all Geological Conservation Review (GCR) Sites in Wales. The boundaries define the area of a particular GCR Site (usually coincident with the geological feature as defined by Common Standards Monitoring). Proposed, current and denotified boundaries are included. Records originally collected to show the extent of GCR blocks. These blocks represent important geological or geomorphological topics (e.g. Mineralogy), geological time divisions, stages and series (e.g. Llandeilo), and areas of search (e.g. South Wales and the Mendips).