Highway Ljubljana - Postojna

Driving on the highway Ljubljana-Postojna, you can get acquainted with some typical karst phenomena. From the Ljubljana basin, wetland on the south and formed as a result of slow tectonic subsidence, the road leading into town Vrhnika, located at the foot of limestone mountains. Powerful Lyublyanitsskie sources (Ljubljanica River, a tributary of the Sava), which extend along the edge of the highlands, is nothing but a karst springs, in other words, underground rivers, pouring here on the surface. Research has established that the river is beer, which we will see, driving another 20 miles in the cave of Postojna - Yama, also carries its waters into Ljubljanica. At 10 km north of Postojna, Planina in the middle of the mountains at an altitude of 450 m above sea level suddenly look opens a vast cavity size 4,5 x 2,5 km with steep sides and flat bottom, so-called Polje, on which meanders flowing river and this land part of the underground waterway that connects with Beer Ljubljanica. Here, if the window is visible portion of the underground karst river network. The people of this, of course, did not know (and even now, scientists do not yet know the details of this complex system of underground waterways), and therefore gave the river with a length of 5 km, own name-ounce. It originated as a Karst spring in the southern outskirts of polya and disappears in the northern slope. Polya bottom is covered with 2 -5 - m thick clay, does not pass water. After heavy rain there is formed a small lake (during the year it exists in an average of about 6 weeks). Such soil Polje can be used for farmland, "Polje" in - Slovenian means "arable land".