Radulja is a creek of a few dozen kilometres, and is a left tributary to the River Krka. In the upper part of its stream, it creates small, but loud and effervescent waterfalls, in a short but wild canyon with almost vertical walls. The Radulje Gorge, the walls of which are about 100 m tall, therefore starts at Klevevška Toplica. Here, Radulja created a deep cut into a layer of triadic limestone, and conquered the steep landscape with numerous small waterfalls. In the winter, these become encased in ice, and can be quite loud in the spring and summer. The nearby settlement of Klevevž was named after the loud rapids; the German word Klingenfels means “singing waterfalls”.