[1] The river has carried rock debris, soil and parts of trees and plants from the mountain range of Aroania (also known as Chelmos, Χελμός), to deposit it in the valley.

At the confluence of the small rivers Λαγκάδα, Ξηρόρεμα and Kleitoras, coming from the carbonate mountains in the west, their alluvial fan expanded the valley drastically.

[4] Pausanias (110-180 AD) in his book “Description of Greece” (Ancient Greek: Ἑλλάδος Περιήγησις) already used the name “Aroanios” for the valley's river.

[5] The preserved publications of Polybios (208-125 BC, “Historíai”) and of Pliny The Elder (AD 23-79, “Naturalis historia”) confirm Pausanias’ description, but are less precise and informative.

The cited ancient book authors also report on the antique city Cleitor as predecessor of modern Kleitoria - again Pausanias is the most precise.

[8] According to this study the waters of the outlets emerge directly from local karstic rock layers, which outcrop here, or they rise from the loose Sedimentation (Silicate minerals, sand and gravel).