Aspects of Aerial Laser Scanning when exploring unknown archaeological sites (Case study)

Obtaining geographical information on the Earth's surface can be very costly and tedious. For this reason, remote sensing methods are increasingly used for these purposes, which allow the acquisition of terrain information via devices most often placed on board of aircraft or satellites. Currently, aircraft carriers are not used only for the acquisition of image data through aerial photography, but they can also carry on board other devices to obtain data of a different nature. This device can be an aerial laser scanner—LiDAR (Light Detection and Ranging) that scans the terrain and objects on the surface with a high precision. It is an active method of remote Earth survey based on the measurement of the distance between the object under investigation and the aircraft itself. The result of this process is a set of precise georeferenced points, which is referred to as a point cloud. By using spatial analyzes, it is possible to use various post-processing methods and it has applications in areas such as forestry, archeology, hydrology, etc. This paper is devoted to the use of Aerial Laser Scanning (ALS) for the purpose of archaeological research on the case study of the Molpír hillfort which is situated at the eastern foot of the Little Carpathians. For collecting the data, the PA-34 Seneca aircraft carrier was used and equipped with the Trimble Harrier 68i advanced mapping system. In the past, several archaeological surveys have been conducted in this area by using terrestrial measurements, however ALS has provided a different view and has enabled identification of sites which have not been previously identified and examined.