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Unica (river)

The 883rd longest river in the world

km

The Unica is a river in Slovenia. It starts as the underground confluence of the Pivka and the Rak in Planinska jama. This is the largest confluence of underground rivers in Europe. 300 meters (980 ft) further, the Unica emerges near Planina. It flows north through the Planina Karst Field (Planinsko Polje) through the municipalities of Postojna, Cerknica, and Logatec, where it returns underground. It then flows for about another 10 kilometers (6.2 mi) underground, emerging 142 meters (466 ft) lower at multiple springs near Vrhnika to form the Ljubljanica River.

Flows through: Slovenia.

River data from Wikidata (CC0); lengths normalised to a common unit.

Other major rivers

  1. Amazon6,992 km
  2. Nile6,650 km
  3. Yangtze River6,300 km
  4. Bian River5,806 km
  5. Yellow River5,464 km
  6. Paraná River4,880 km
  7. River Congo4,700 km
  8. Mekong River4,350 km