The origin of hydrothermal karst cavities was connected with the Variscan hydrothermal process. The cavities were formed and filled by crystalline calcite. The process was accompanied by the intensive dolomitisation. Younger phase of hydrothermal karstification was not connected with vein-filling, but with the deep circulation of groundwater, probably associated with neovolcanic activity in the Bohemian Massif. This is supported by pollen grains and decomposed volcanic ash in speleothems which were formed after the major phases of speleogenesis. It is supposed that caves in the Konûprusy Devonian were formed in confined aquifer under phreatic and batyphreatic conditions. Thermal conditions appeared when paleogeothermic gradient was increased due to intensive neovolcanic activity. Hydrothermal karstification partly changed the morphology of caves. The maximum temperatures were stated to 60-700 C from large calcite crystals precipitated under phreatic and deeply phreatic conditions. The piezometric level was situated above limestones in Upper Cretaceous platform siliciclastics as indicated by numerous subvertical phreatic tubes („depressions") filled with sunkened Cretaceous and Tertiary sediments after the water buyoancy support decreased. Popcorn-like silicified Konûprusy Rosettes can be result of decrease of thermal water level and mixing with infiltrating meteoric waters. Outer zones of large calcite crystals with precipitation temperatures of about 400 C can indicate the gradual cooling of the whole system.

Progress in the understanding of cave genesis processes, as well as the intensive research carried out in the Alps during the last decades, permit to summarize the latest knowledge about Alpine caves. The phreatic parts of cave systems develop close to the karst water table, which depends on the spring position, which in turn is generally related to the valley bottom. Thus, caves are directly linked with the geomorphic evolution of the surface and reflect valley deepening. The sediments deposited in the caves help to reconstruct the morphologic succession and the paleoclimatic evolution. Moreover, they are the only means to date the caves and thus the landscape evolution. Caves appear as soon as there is an emersion of limestone from the sea and a water table gradient. Mesozoic and early tertiary paleokarsts within the alpine range prove of these ancient emersions. Hydrothermal karst seems to be more widespread than previously presumed. This is mostly due to the fact that usually, hydrothermal caves are later reused (and reshaped) by meteoric waters. Rock-ghost weathering is described as a new cave genesis agent. On the contrary, glaciers hinder cave genesis processes and fill caves. They mainly influence cave genesis indirectly by valley deepening and abrasion of the caprock. All present datings suggest that many alpine caves (excluding paleokarst) are of Pliocene or even Miocene age. Progress in dating methods (mainly the recent evolution with cosmogenic nuclides) should permit, in the near future, to date not only Pleistocene, but also Pliocene cave sediments absolutely.