The Pivka is a karst

KARST

Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...

 lost river

Losing stream

A losing stream, or influent stream, is a stream or river that loses water as it flows downstream. The water infiltrates into the ground recharging the local groundwater, because the water table is below the bottom of the stream channel...

 in Slovenia

Slovenia

Slovenia , officially the Republic of Slovenia , is a country in Central and Southeastern Europe touching the Alps and bordering the Mediterranean. Slovenia borders Italy to the west, Croatia to the south and east, Hungary to the northeast, and Austria to the north, and also has a small portion of...

. The river is 27 kilometres (16.8 mi) in length. The Pivka ends in Planina Cave, where it merges with the Rak River and then the Unica River. The confluence of the Pivka and the Rak is the largest subterranean confluence in Europe. The Pivka created Postojna Cave

Postojna Cave

Postojna Cave is a 20,570 m long Karst cave system near Postojna, Slovenia. It is the longest cave system in the country as well as one of its top tourism sites.-History:The caves were created by the Pivka River....

, the longest cave system in Slovenia as well as one of its top tourism sites

Tourism in Slovenia

The Central European nation of Slovenia offers tourists a wide variety of landscapes in a small space: Alpine in the northwest, Mediterranean in the southwest, Pannonian in the northeast and Dinaric in the southeast....

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