Common availability of LiDAR data - high-quality digital elevation data, with a vertical accuracy of approx. 0.15 m and horizontal resolution of approx. 0.5 m makes, that very precise geomorphometric calculations of the relief (or microrelief) of different areas becomes possible. This work is part of the current research tendency related to find some kind of indicator which can quantitatively describe the diversity of the surface relief. Sometimes in geomorphology were used terms as relief intensity or energy of relief (Szczepankiewicz 1948, Szumowski 1967, Grygorenko 1973, Richling 1973, Kaulfuss 1974, and others) or elevation-relief ratio (Pike, Wilson 1971) based mainly on the relative heights, slopes, or the number of depressions. Relief Index (RI) is a simple mathematical tool which characterizes the quantity of relief. This index is based on the ratio of the summary length of the contour lines and the surface area at which they occur.