Caves evolve due to various geomorphological processes which can be used to develop a classification scheme. We adapted existing genetic classifications and focused on the main genetic process which we defined as the one that was responsible for most of the cave volume. This scheme was applied to the 4,849 known caves of Lower Austria and some neighbouring areas. It turned out that more than half of the caves have developed due to weathering and erosion and only 45 % are karstic ones.