The Nišava originates in western Bulgaria, in the Stara Planina mountains (east of Kom Peak) near the village of Gintsi.

It first flows to the south, then sharply turns west into the Godech Kettle, passing through Razboishte, after which it forms a gorge.

With the rapid growth of Niš in previous decades and its still fast growing suburbs, the banks of the Nišava are urbanized almost to its mouth.

Its own drainage area covers 4,086 square kilometres (1,578 sq mi), of which about 73% is in Serbia, the rest in Bulgaria.

In its Serbian part, the Nišava has carved a composite valley with several depressions (Dimitrovgrad, Pirot (or Basara; Cyrillic: Басара), Bela Palanka and Niš).

It was suggested that some kind of contact of different species of humans happened in the region, one group being from Europe, and the other coming from Asia Minor.

[5][6][7][8] On the southern side of the river, on the Suva Planina, there is a Pešturina cave, nicknamed the "Serbian Atapuerca".

[10] The remains, identified as the Mousterian culture, were dated from 102,000 BP+ 5,000 to 39,000 BP + 3,000, which makes Pešturina one of the latest surviving Neanderthal habitats.

All Paleolithic sites in the Central Balkans, including discoveries in the Nišava valley, have the noticeable absence of the Aurignacian layers.

That points to the theory that the expansion of the early modern humans into Europe occurred via the Danube corridor, which allowed for the small Neanderthal communities to survive beyond 40,000 BP in some isolated pockets.

[16] In 2008, cultivation of various aromatic and medicinal herbs began in the Serbian section of the Nišava watershed and the valleys of its tributaries.

Other herbs include Roman chamomile, dwarf everlast, lemon balm, hyssop and Damask rose.