In: Wagner W., Szekely, B. (eds.): ISPRS TC VII Symposium - 100 Years ISPRS, Vienna, Austria, July 5-7, 2010, IAPRS, Vol. XXXVIII, Part 7B 
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particularly useful in areas with a large percentage of mixed or 
deciduous woodland; it is less effective in dense conifer 
plantations and indeed is only really successful if flown at the 
correct time of year when there is minimal vegetation cover. 
When used in the right conditions, however, the results can be 
dramatic. Savemake Forest is an area of ancient woodland that 
had been established as a royal hunting forest by the time of the 
Domesday survey in 1068. It is now an area of largely 
deciduous woodland managed by the Forestry Commission 
covering an area of some 40 sq kms that is used both as a 
timber resource and as an area for recreation. As part of a new 
management plan the Forestry Commission decided to 
commission a lidar survey to record the area and English 
Heritage worked in partnership with them to map the area as 
part of the National Mapping Programme (NMP) (Bewley 2001 
& 2003). Using a combination of lidar data and traditional 
aerial photographs, including historic imagery dating back to 
the 1930s, over 300 new sites were recorded, doubling the 
number of known features in the survey area. Some of the most 
important sites recorded were a potential early roman temple 
complex and several new prehistoric settlement enclosures (Fig 
1). As well as these entirely new features the survey also added 
considerable detail to the Roman roads that run through the 
survey area (Crutchley et al 2010). 
Figure 1 - A late Iron Age enclosure in Savernake 
Forest seen in first return (left) and last return (right) 
lidar data, (lidar © Forestry Commission; source, 
Cambridge University ULM (May 2006)). 
3.2 Uplands 
The other sphere where lidar has proven to be particularly 
useful is in areas of extensive upland archaeology. This is rather 
different from woodland survey where lidar allows the 
recording of features that would otherwise be extremely 
difficult even to see, let alone record; in upland areas the 
features are generally visible on the ground and could be 
recorded using traditional techniques, but the use of lidar makes 
surveying much quicker and more efficient. An area of the 
North Pennines is being mapped as part of a multi-disciplinary 
project entitled “Miner-Farmer landscapes of the North 
Pennines Area of Outstanding Natural Beauty (AONB)” that 
evolved from the management plan for the AONB. The 
landscape is sparsely settled with considerable height variation 
between the valleys and the unenclosed moorland The area is 
being surveyed using a combination of lidar and other remote 
sensing techniques and then mapped as part of NMP using a 
combination of this data and what traditional aerial photography 
of the area exists. Detailed analytical fieldwork is then being 
undertaken for the core project area, taking printouts of the lidar 
data and desk based interpretations into the field for further 
analysis as well as identifying features not seen on the lidar 
data. Apart from revealing features that are difficult to identify 
on much of the traditional aerial photography, the lidar data is 
also proving useful as it provides an extremely accurate base 
map against which other sources can be registered and mapped 
(Fig 2). 
Figure 2 - Using lidar as control 
Lidar also allows the accurate mapping of extensive features 
such as the remains of the mining industry that would otherwise 
take a long time to survey on the ground and therefore enables 
field survey time to be concentrated on those areas identified as 
most important or too confusing from the lidar data alone. 
3.3 Environment Agency standard image tiles 
Whilst English Heritage has mainly been working with the lidar 
data specifically captured with archaeological use in mind, we 
have also been examining the use that can be made of the 
readily available data that has been collected by other agencies 
for non-archaeological use. The largest example of this in the 
UK is the Environment Agency, the body with the role “to 
protect and improve the environment, and to promote 
sustainable development”. One of their key areas of interest 
relates to flood management and to this end they have been 
carrying out lidar surveys around the UK for over ten years; 
they have concentrated mainly on the coast and major river 
valleys to record the topography and how this relates to possible 
flooding. They have established a reference archive of lidar 
derived imagery as a series of georeferenced image tiles 
covering on average 1 - 4 sq km. These tiles are created as 
hillshaded images and are colour coded according to a 
consistent set of height gradients. On first viewing, often these 
do not reveal very much archaeological information, but with a 
little simple manipulation within Adobe or another standard 
image processing program it is possible to bring out features of 
archaeological interest not necessarily visible on standard aerial 
photographs. Although this is not as effective a method as full 
manipulation of the source lidar data, it does provide a quick 
and easy way into the data that is useful for preliminary 
archaeological survey.