What is LiDAR?
LiDAR, standing for “Light Distance and Ranging,” also known as Airborne Laser Scanning (ALS), is a survey technique that has been used by archaeologists for just under 20 years now. It has aided in the discovery of new sites, and is particularly important for its ability to show archaeology beneath vegetation.
The technique works using a plane-mounted laser scanner which sends out millions of pulses of light towards the ground and detects the reflections. From this data a highly accurate “point cloud” is created of everything the light has hit on the earth’s surface. The points are then ‘classified’ for whether they are vegetation, buildings, or the ground surface; all of the above-ground points are filtered away, leaving us with a “digital terrain model” of the bare earth, which allows us to start to detect archaeology!
Our LiDAR Survey
In 2018/19 we commissioned a bespoke survey of the Chilterns and some surrounding areas. At 1400 km2, it was the largest LiDAR survey ever flown for archaeology in this country, and one of the largest in the world. The survey took place over the winter, with the data available through our Citizen Science LiDAR Portal.