Archaeologists using LIDAR (LIght Detection And Ranging) have located prehistoric burial mounds in the New Forest, Salisbury (England). Discovering such sites in a wooded setting such as the New Forest would normally be time consuming and require exhaustive ground-based field-surveying techniques.
     LIDAR is a 50-year detection technology originally used to discover submarines. Archaeologists have begun to discover its applications for discovery only within the last 10 years. LIDAR employs a pulsed laser beam which sweeps from side to side as a plane or helicopter flies over the area of interest.
     Archaeological researcher Tom Dommett states, "One of LIDAR's greatest benefits in the Forest is its ability to penetrate all but the densest vegetation like conifer or holly. It reveals very subtle features which are difficult to see on the ground and are even more dificult to map accurately, particularly in woodland."
     It should be noted that often a potential archaeological site that has been picked up by LIDAR needs to be verified by a focused small-scale field survey, known as ground-truthing, because the technology can be indiscriminate in what it shows. The application of LIDAR, however, can greatly accelerate the surveying process archaeologists utilize.
     "At the current rate of survey carried out in the National Park it would take roughly 200 years to obtain a full understanding of the archaeological resource, but with lidar we will hopefully be able to do it in 10 years," Dommett concluded.

Source: The Salisbury Journal (3 June 2010)