The riverbed of the river Krka is composed of many natural thresholds, which are sheated in tufa (a variety of limestone). Many pools and cascades are overgrown with green moss and offer many hiding places for the fish. The water temperature is relatively stable, so that the living conditions for fish are always optimal. In spring and early summer, when the Mayflies, sedges and stoneflies emerge, the fishing with dry flies is extremely successful. The best time for fishing is the beginning of April to the end of June. In April, around noon, when the warm spring sun encourages the swarming of the flies, is the exactly right time for fishing with dry flies. In the warm April evenings the evening rise begins, which then culminates in May and early June. An evening rise on a warm evening lasts late into the night.