The lake is most important hydrogeological feature of the park and indeed entire Dinaric Alps karst within Bosnia and Hezegovina.

The lake area varies from 2.5 to 6 km2, and the average depth is about 1.9 m. Blidinje lake is direct result of a glacial retreat, however, according to the Poklečani parochial office documents and recent research into matter of karst hydrology of the plateau, the lake is, also, a product of anthropogenic intervention and activities of human inhabitants.

According to these documents, the lake is artificial and it was created at the end of the 19th century.

In order to keep the water that is lost through the subterranean passage, local residents and cattle breeders sealed sinkholes with branches and clay, so that water could not find its way underground.

Its surface area varies between 2,5 and 6 km2, while its average depth is 1,9 m, with altitude of 1.184 m a.s.l.