Blooming of the Ukrina River

Another specific feature for which Derventa is widely known is the phenomenon of the so-called “blooming of the Ukrina River” (water flower phenomenon). This is a phenomenon occurs in summer evenings and nights in late August, when above and around watercourses swarms of aquatic insects-butterflies appear.

These insects live for three years as a larva at the bottom of a river and they only spend a few hours of life over water in order to mate and do the thing they are preparing for their entire short lives – procreate their kind