Pomponius Mela describes its ancient names as being so called because it has a great fall or cataract.
Through this calcareous crust the water finds its way to the sea, and the river has now no determinate outlet, unless, adds Leake, it be after heavy rains, when, it precipitates itself copiously over the cliffs near the most projecting point of the coast, a little to the west of Laara.
These sources, Kırkgözler (around 37°05′45″N 30°34′51″E / 37.0957°N 30.5807°E / 37.0957; 30.5807) and Pınarbaşı (37°10′00″N 30°35′58″E / 37.1667°N 30.5994°E / 37.1667; 30.5994 [citation needed]), merge after a short flow and disappear into Bıyıklı Sinkhole (37°06′09″N 30°36′59″E / 37.10241°N 30.61642°E / 37.10241; 30.61642).
Part of the water is diverted through a canal from the Kirkgöz Springs to a reservoir at 36°57′14″N 30°37′43″E / 36.95397°N 30.62860°E / 36.95397; 30.62860, from where it drops 162 metres (531 ft)[4] through an underground pipe into Kepez 1 Hydroelectric Power Plant (36°56′27″N 30°37′26″E / 36.9407°N 30.6238°E / 36.9407; 30.6238).
The waters of the river separate into a number of streams and finally, east of Antalya, cascade 40 metres (131 ft) from a platform into the Mediterranean as the Lower Düden Waterfall (36°51′03″N 30°47′00″E / 36.85093°N 30.78337°E / 36.85093; 30.78337).