Iška and Zala are mountainous watercourses whose tributaries have carved distinctive gorges in the dolomites and limestones. Zala originates on the western edge of the Vid plateau, and Iška on the northern side of the Bloke plateau near the settlement of Lužarji. Many smaller springs feed the Iška already in its middle course into a mightier stream, which flows through numerous rapids and cascades toward Vrbica, where it joins Zala. The watercourse, with the common name Iška, then runs through the Iški vintgar gorge toward Iška vas village and on toward the Ljubljana Marshes.
