The Sava Dolinka rises at the Zelenci Pools near Kranjska Gora, Slovenia, in a valley separating the Julian Alps from the Karavanke mountain range. The spring is near the Slovene-Italian border at above sea level, in a drainage divide between the Adriatic and Danube basins. The Sava Dolinka spring is fed by groundwater possibly exhibiting bifurcation of source karst aquifer to the Sava and Soča basins. Nadiža creek, a short losing stream flowing nearby, is the source of Zelenci Pools water. The Sava Dolinka is considered the Sava's initial, segment.