Krka is famous as the only tufa forming river in Slovenija because in the upper stream it forms characteristic, up to several metres tall tufa barriers, by which watermills arose; in the mid stream tufa is secreted just below the surface in the shape of extensive underwater thresholds. Most extensive thresholds can be viewed in Krka's mid stream just outside Otocec, where the river valley cuts into a higher limestone plateau. Tufa thresholds are extending in between Otočec village and Struga castle for almost two kilometres, and the rivers drop in this area reaches four metres.
On top of the thresholds islands were formed, that were settled by a great variety of riverside vegetation. Island forming is a dynamic process as high water lessens their size and on the other hand exuberant vegetation stops the alluvium and forms new fragile riverbanks. During midseason you can count up to 30 islands between Otočec village and Struga castle, the greatest of them is castle island.
For tours the most appropriate are walkways around Otočec castle and the road connecting Otočec and Struga.
Free of charge
GPS Northing (N) : 45,8367
GPS Easting (E) : 15,2282