The Paklenica karst river canyon is a national park in Croatia. It is located in Starigrad, northern Dalmatia, at the southern slopes of Velebit mountain, not far from Zadar. It has two canyons: Mala (Small) and Velika (Big) Paklenica. Today there is no water flowing throughout Mala Paklenica. Near the entrance into the Velika Paklenica there is an artificial basement/cave complex that had been built for Josip Broz Tito during the tension between Yugoslavia and the USSR in the late 1940s and early 1950s.

http://en.wikipedia.org/wiki/Paklenica