Britain was the first country to take up aerial exploration after World War II, and has since carried this activity to new levels of effectiveness and sophistication (for a general account of
developments and results in England, for instance, see BARBER
2010). Though many other European countries make wide use of archaeological air photography the integration of the
technique into the fabric of public archaeology (and to a lesser extent into academic studies) is at its most developed in Britain.
Whereas mapping and topographical studies were the driving force behind post-war developments in Italy, the impetus in Britain came in the first instance from the irresistible lure of exploration.
Dr (later Professor) J. K. S. St Joseph (Fig. 1.13) first began aerial exploration before the war with O. G. S. Crawford. During the war, amongst other things, he undertook intelligence work and flew as observer on a number of Royal Air Force (RAF) missions. Through his wartime contacts he persuaded the RAF to take him on further flights in the post-war years as passenger and photographer, recording whatever archaeology or other subjects he could. In 1948 he began survey work for the
University of Cambridge, the position being formalised in 1949 with the establishment of the Cambridge University Committee for Aerial Photography (CUCAP) to provide air photographic material for all departments of the university. For many years,
therefore, St Joseph photographed topographical, geological or geomorphological features as well as archaeological sites (he was himself a trained geologist).
In 1965 the Cambridge unit acquired its own aircraft and began free-ranging flights in response to requests or in pursuit of
particular research interests, notably, for instance, the surviving (or still hidden) evidence for Roman military campaigns in
various parts of Britain. Exploratory campaigns were also undertaken in other countries, for instance in Ireland between 1951 and 1973 as well as in Northern France (1961, 1973-74), Denmark (1966-70) and the Netherlands (1970-73). By the time the unit drastically reduced its work on oblique aerial
photography in the early 1980s (in favour of commissioned vertical photography for a wide variety of purposes) the number of oblique photographs in the Cambridge collection amounted to some 300,000 (not all of them archaeological), covering most of Britain as well as parts of Ireland, France, the Netherlands and Denmark. The discoveries made over the years revolutionised the content and understanding of the Roman occupation of Britain, and brought vast quantities of new data (and new interpretations) to almost every period of British antiquity from the Neolithic to the rapidly changing rural and industrial scene of the twentieth century (see, for instance, NORMAN–ST JOSEPH
1969; BERESFORD–ST JOSEPH 1979; FRERE–ST JOSEPH 1983;
HUDSON 1984). The unit was later absorbed into the university’s Department of Geography as the short-lived Unit for Landscape
Modelling. The photo collection can still be consulted in person or over the internet through its computerised catalogue
(www.geog.cam.ac.uk/cucap).
In the post-war years British aerial photography also benefited from the efforts of a small but energetic band of ‘private flyers’, notably Arnold Baker, Jim Pickering and from the 1970s to his death in 1993, Derrick Riley (Fig 1.13). These dedicated
researchers used aero club aircraft and their own funds to scour the countryside, and of course to integrate their
discoveries into the archaeological concepts of the time (for some of Riley’s work see Figs 9.4 and 9.6). Later, when limited funds became available from public sources, these few
pioneers were joined in the air by others whose daytime jobs lay for the most part in museums, local authorities and
university departments. For a time, as a result, Britain had an informal pattern of ‘regional flyers’ who covered those parts of the country not adequately dealt with by the national survey organisations.
The biggest players on the national scene are now the state-backed survey bodies known as the Royal Commissions, in the case of England now subsumed within a larger body, English Heritage. The English Commission was the first to take up aerial survey, establishing an Air Photographs Unit in 1965 and
beginning its own flights two years later. The Scottish
Commission followed suit in 1976 and the Welsh Commission in
1986. All three bodies undertake their own survey flights, using hired aircraft both for exploratory work and for a variety of other functions in the fields of recording and conservation. English Heritage also provides part-funding for the work of a small number of county-based regional flyers. All of the photographs produced at national and regional level are on public access through county, regional and national archives. All three
Commissions (and a number of other bodies across Britain) hold substantial archives of ‘historical’ air photographs, both vertical and oblique, derived from a variety of sources, notably the vertical coverage created from the mid-1940s by the RAF and from the mid-1960s to the late 1980s by the Ordnance Survey.
After that date most of the Ordnance Survey’s mapping work was done directly from negatives; both these and the digital
images acquired in place of negatives from the early years of the new century, have to be printed before public access can be provided.
The emphasis on topographical analysis and mapping which still dominates aerial archaeology in Italy found its counterpart in Britain in the policy of John Hampton, the first head of the Air Photography Unit in the Royal Commission in England. He insisted that as many photographs as possible should be
converted into ‘cartographic statements’, at a variety of scales, so that they could be read like any other mapped or
documented information used by archaeologists. This led in the late 1980s to pilot studies that developed from 1992 into a
National Mapping Programme for England (NMPE), the aim
being to create maps and written records for all disused features of the landscape that can be seen on vertical or oblique aerial photograph over the whole of the country (Fig 1.14; BEWLEY 2001; HORNE 2009, 2011; WINTON–HORNE 2010; web reference NMPE). Projects within NMPE invariably increase the number of known ‘sites’ in an area, with particular gains in the medieval, post-medieval and recent periods. Often the ‘new’ sites
represent 60-70% of the records at the end of a mapping exercise. The Welsh and Scottish Commissions have taken rather different lines, their mapping projects being more closely related to survey work on the ground or to the transcription and description of the individual sites recorded during exploratory survey.
Britain has no institution specifically devoted to aerial
photogrammetry for archaeology, though photogrammetric mapping was in the 1980s and 1990s carried out on a selective basis by English Heritage, mainly for sites which had special management needs or which were the subject of complementary analytical survey on the ground. In most of Britain, however, the concentration is on the fairly rapid interpretation and computer-based transcription of archaeological information, at a basic
scale of 1:10,000, from both vertical and oblique photographs, so as to create ‘landscape-scale’ rather than ‘site-based’ maps for incorporation, along with related text records, in GIS systems
providing information on all aspects of the archaeological resource.
To an extent this policy can be traced back to the realisation, especially in the early 1970s, that vast amounts of
archaeological information were being lost to construction works, industrial development, road building, afforestation and the like.
From this growing public and political awareness of the need for
‘rescue archaeology’ there came a rapid growth in the number of archaeologists working within county and municipal authorities to document and map the known archaeology so that it could be protected (as far as possible) through the development control and other planning procedures. A necessary tool was the
municipal, county or regional Sites and Monuments Records (SMRs), more recently expanded in scope to form so-called Historic Environment Records (HERs). From the outset these consisted of basic maps and text descriptions of all the
archaeological sites and finds, of all dates until relatively recent times, that could be identified in the available sources (aerial photographs included). The creation of these records from the mid 1970s onwards, and their progressive transfer to GIS-based systems in recent years, has shown how important it is to have basic information about all known sites, rather than just detailed data on a favoured few. One upshot of this approach, and of its reflection in policy for air photo mapping, has been the regular use of aerial information to identify the implications of
development proposals, especially those involving large tracts of
The state of completion, at the beginning of 2013, of the English Heritage project for the (now digital) mapping at 1:10,000 scale of all traces of archaeological
significance observable on readily available vertical and oblique aerial photographs of England.
In recent years the focus has been on parts of the country that are considered most at risk from
archaeologically damaging factors such as coastal erosion, heavy agricultural activity or industrial and urban expansion.
The results of the work in the individual study areas can be consulted on the project website at
english-heritage.org.
Fig 1. 14 The National Mapping Programme for England (NMPE)
On the left is a detail from a multi-spectral image acquired by the QuickBird 2 satellite near Pienza. On the right (printed here at a larger scale) is part of the same area recorded by the satellite’s panchromatic sensor. In both images it is possible to make out a linear mark oriented WNW-ESE, a diversionary route of the Via Cassia. In the image on the right the level of recorded detail is good enough to show the white line along the centre of the road near the bottom of the picture.
Fig 1. 15 Satellite imagery
land, such as major industrial developments, road building
Cathy Stoertz, of English Heritage, with the ‘red boxes’ which contain the 35,000 individual images which she used in creating the series of interpretative maps presented in her study of the chalk downland of the Yorkshire Wolds, in northern England. See also Figs 9.8, 9.9 and
STOERTZ 1997.
Fig 1. 16 Interpreting and converting photographs into maps
projects or pipeline construction. Both existing and newly commissioned aerial photographs, and their analysis and
transcription at varying map scales, have become regular tools in the conservation process, the mapped information often providing the broader context for detailed excavation evidence where salvage work still proves necessary (Fig 2.21).