The pleasant Nordic hike can also be combined with exploring the rich natural heritage. The Otok Tržič ("Tržič Islet") Nordic trail takes us to the Krka River, the only Slovenian river that forms tufa deposits in its riverbed. The carbonate rocks and favourable climate gives rise to the formation of tufa, which accumulates in the river in the form of barrages, thresholds, sills and islets. The Otok Tržič islet near Dolenje Kronovo is the largest of these sediment formations. When the water level is low during the summer, you can roll up your trousers and wade across the Krka right up to the islet. The most persistent of you might be rewarded by spotting a kingfisher.