Field and as mineralogical and petrographical examinations of sedimentary rocks present in the area surrounding the Pieniny Klippen Belt were performed. The aim of these investigations was to identify the symptoms of hydrothermal processes within the studied rocks. Moreover, the areas prospective for the occur- rences of geothermal waters, alternative source of thermal energy instead of traditional power production using fossil fuels, were indicated. Analytical investigations were focused mainly on mineralogical composition of rocks as well as on the frequency of occurrences of various veins (mainly built of carbonate minerals) intersecting the rocks from the neighbourhood of Neogene andesitic rocks from the Pieniny Klippen Belt. The highest quantity and thickness of the veins was observed in the rocks from the area of Piekie ko stream near Kro cienko. The clastic rocks (sandstones) from this area contain many fractures which are crucial for potential geothermal water circulation.