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This paper presents the use of archival stereo pairs of aerial photographs from years 1965 and 2002 to assess the dynamics of an active landslide "Śliwnica" located on the Dynów foothills. Two photogrammetric digital terrain elevation models were generated. Then, by comparing the spatial relief digital terrain elevation models, the map of differential displacements of rock masses was generated with GIS system. It reflects the dynamics of the spatial displacement of rock masses within the landslide. In addition, cross-sections were performed by different geomorphological digital terrain models to assess the differences in terrain. For example, a cliff in Jastrzębia Góra shows the application of stereo pairs of aerial photographs and digital terrain model LIDAR (Light Detection and Radar) to determine the dynamics of coastal cliffs and identification of landslides. Stereoscopic effect disturbed by the vegetation lush, but in spite of these shortcomings managed to reach the edge of the cliff set was possible to determine. Images were analyzed at different magnifications in order to commit the slightest error. It was found that between 2004 and 2011 the edge of a cliff in the area Jastrzębia Góra moved up to over 19 meters. At the same time the analysis of the digital terrain model derived from airborne laser scanning showed activation of the three landslides that threaten the surrounding infrastructure. Digital model derived from airborne laser scanning can determine the precise extent of landslides, slope and slope primary and secondary data provides many landslides morphometry. The advantage of this method is the ability to filter data and therefore to eliminate the vegetation. Skilful interpretation of the terrain can efficiently speed up field work and thus reduce the cost of research.
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