A Buffer Zone is an area surrounding the World Heritage Site that gives an added layer of protection to the Site.
Buffer Zones should include the immediate setting of the nominated Site, important views and other areas or attributes that are functionally important as a support to the Site and its protection.
In order to meet UNESCO requirements, a Buffer Zone should be clearly delineated on a map and have an associated policy to indicate the area where development may adversely affect the setting of the WHS. The Buffer Zone can be used to highlight an area where potential impacts need to be given careful consideration by developers and decision-makers.
Although Buffer Zones are required to have complementary legal and/or customary restrictions placed on their use and development they are not formally a part of the inscribed World Heritage Site.
The Buffer Zone for the Antonine Wall has been defined to protect the immediate setting of the WHS; the adjacent environment that is part of, and contributes to the character, significance and understanding of the Wall. Definition of the Buffer Zone has been based on visibility to and from the WHS, and analysis of the land use setting, including urban areas.
This was carried out using available data relating to the WHS and its surroundings, Geographical Information Systems (GIS) intervisibility analysis with the surrounding landscape, and site survey work. On the ground, the Buffer Zones were defined by following permanent and obvious markers in the landscape such as roads, railways and established field boundaries. Where man-made boundaries were not available, other readily recognisable features such as streams and rivers were used.
Understanding of the landscape in which the Antonine Wall sits was aided by two landscape projects; the landscape characterisation assessment undertaken by Scottish Natural Heritage and the Historic Land-use Assessment undertaken by Historic Scotland and the Royal Commission on the Ancient and Historical Monuments of Scotland.
The Buffer Zone has been defined as a series of zones along the Wall, up to approximately 1-1.5 km from the Wall to the north and south. These areas are fragmented by existing settlements, roads and areas marked for urban expansion.
Fourteen zones have been described, including small parks or open spaces with settlements. In order to maintain a general constancy of width, and to create a robust planning boundary that can be more strongly defended, the buffer zones have been defined as tight areas around the archaeological remains, and boundary features include roads, railways and the Forth and Clyde Canal.
The WHS itself is 526.9 ha in size, the Buffer Zone is 5229 ha. The full mapping for the WHS and its Buffer Zone can be found in the 2007 WHS Nomination Document presented to UNESCO.