Wanstead Park laid bare: laser technology reveals a hidden landscape

The Wanstead Parklands Community Project has taken the lead in recent years in researching the long history of Wanstead Park using cutting-edge archaeological surveying techniques. On 9 July it will be using its stand at the 2011 "Music in Wanstead Park" as a showcase for its latest initiative, an investigation of surviving landscape features using Light Detection And Ranging (LiDAR) technology.

LiDAR is an optical remote sensing technology that can measure the distance to, or other properties of, a target by using pulses from a laser. Its great advantage is that it can produce "bare earth" terrain models which strip away vegetation cover. The data produced can be manipulated with visualisation software to enable the user to choose the angle and direction of apparent illumination. The vertical scale can also be exaggerated, thus showing up any slight irregularities in the ground to best advantage. Aerial photographs and other data can be draped on top of the terrain models.

Having recently obtained a full set of LiDAR data for Wanstead Park, we have had the good fortune to recruit Dr Rob Wiseman, who has produced an extraordinary range of images using Landserf analysis and visualisation software. The images shown here are, of course, at much lower resolution than the originals.

The terrace upon which Wanstead House once stood, and the parterres which flanked it, are shown very clearly, as well as garden features which are currently smothered in vegetation. Many very subtle features may be seen which are almost invisible at ground level.

As well as the famous gardens, it is possible that LiDAR may shed some light on the park's early history - the Plain shows signs that it may have been covered by a mediaeval field system, for example.

As an example of what LiDAR can reveal, we shall focus here on just one pair of features - from an engraving by Jan Kip and Leonard Knyffthe viewing mounts which were constructed around 1713, probably with spoil excavated from the Long Walk. The image - a detail from an engraving by Jan Kip and Leonard Knyff - shows them either drawn from plans or very shortly after their construction.

The next two photographs show the north and south mounts respectively as they are today - deplorably overgrown, their outlines almost indistinguishable.

However, LiDAR shows them to be damaged, but essentially intact.  The photograph below shows The Mount in Lewes, a similar feature which has been maintained and kept clear of vegetation.

Richard Arnopp said: "LiDAR demonstrates just how many features from Wanstead Park's history have survived, even where nearly two centuries of neglect have rendered them almost invisible. It also promises to be a valuable tool in helping us clarify aspects of the development of this unique landscape".