Location: Inner Carniola Map
Area: 38 km²
Email: info@notranjska.eu
Lake Cerknica or Cerniško Jezero is a beautiful pristine lake located in the Inner Carniola region of Slovenia. The lake covers an area of 38 km² with a maximum depth of 10 meters or 33 feet. Unique feature of this body of water is a fact that it is situated over karst cavern. Occasionally the water rushes down inside underground spaces below leaving only marches and wetland above. During wet season the lake fills up again. Water shoots through numerous springs from the subterranean reservoirs below ground level. First man who described this curious pattern was ancient Greek historian, geographer and a traveler Strabo (63 BC- 24 AD. He called it Lacus Lugeus (Mourning Lake) in his book Geography (volume 7, chapter 5). However it wasn't until 17th century when Johann Weikhard von Valvasor explained these intermittent patterns. During dry periods that usually last from June to September the lake dries up leaving large expanses of lands. Locals bring their cattle here and over 200 species of migratory birds begin to nest here. The largest human settlement here is a town of Cerknica. If you want to find out more about the lake you can head to village of Dolenje Jezero (2 mi South of Cerknica) where you can visit Lake House Museum devoted to this famous lake.
Inflows and outflows
All tributaries and drains except Cerkniščica are karst.
On the Loka field, the Obrh brook flows and comes to the surface in
the Cerknica field as the Stržen brook . Water from the underground
flows from the underground of one of the most beautiful water caves
- the Križna jama cave . Cerkniščica and Javornik waters also flow
into the Karst field . All this water flows into the esophagus at
Cerknica Field in several directions: one part flows as the Rak
stream into Rakov Skocjan and further below the earth to the
Mountain Cave where it merges with the Pivka River from Postojna
Cave and flows as a Unica River., the second part sinks towards
Planinsko Polje , the longest path is made by water that comes to
the plan in springs near Bistra .
Cerknica Lake fills mainly after the autumn rains and in the spring
when the snow melts . It dries in May or June and sometimes even in
winter .