ABSTRACT
A major part of Slovenia is built by karstified carbonate rocks. Karst features, solutionally widened fissures, dolines, collapse dolines and caves must be taken into account at the building on karst. The road construction is the most demanding as the roads cannot avoid the karst phenomena. During the work numerous unknown karst cavities are discovered. The most typical examples met at the construction of highway over Kras are described and the mode of solution suggested.
