More detailed understanding of small parts of the historic environment, obtained through techniques like landscape survey, analytical survey, geophysical survey, excavation, architectural investigation and various forms of documentary and cartographic research is then applied to the types identified to extend that generalised understanding.
Characterisation typically covers the whole of an area quite rapidly in order to support a range of partners. They may use characterisation to support management, enjoyment, protection and planning, or to stimulate more detailed research. The material is usually recorded and displayed as polygons on a Geographical Information System (GIS) with information on attributes stored in an attached database that allows queries to be made which then produce maps and other material, as required.
Characterisation has been applied by and for Historic England to historic landscape, the sea, and towns and cities. Characterisation may also be used to model other aspects, such as change (or constancy), present and past activity levels, and the sensed qualities of place, such as sound and smell.
The characterisation approach is closely linked to the development and application of the European Landscape Convention, which has landscape as an area perceived by people. Ways of valuing place vary between individuals and communities and change over time, so fixed measures of significance are not applied to the characterisation material. Instead the attributes that support it can be assessed and evaluated as different issues affect places.