One of the largest fossil landslides dominates the region to the northeast of Ilirska Bistrica, a huge Pliocene calamity that happened over 1.5 million years ago. But this is not the only geological wonder around here. When the Snežnik massif rose and closed the Pivka Valley, the rivers had to change their courses and Reka cut a new route that now ends at the Škocjan Caves. From the Šilentabor ridge, the thrust fault drops precipitously into the Reka Valley. A rare tectonic window lies near the village of Knežak, its geological sequence turned upside down with limestone from the times of dinosaurs at the top, and sedimental flysch remnants of the ancient sea underneath.