The Gradac River Spring
Zabava is the source river of Gradac, which originates from several springs in Kneževo Polje below Mali Povlen (1347 m above sea level), flows through the field like a stream and plunges into a limestone pit at the end of it. It reappears on the surface after about 200m below Bela Stena, as a source of Bela Voda. It got its name only at the German Mills, under the Jelje forest. How the river got its name Zabava, no one knows. There used to be 19 mills and a lot of trout on the river. There is also the hamlet of Zabava near the river. It is interesting that the word (Z)”abava" is an old Serbian word and that in the Middle Ages it meant "Disruption to trade".
There was a pond at the place where it sank, and according to the story, a dragon lived in it, and occasionally went out "to walk" on the low grass of Kneževo Polje. Even today, people report the testimony of the ancients that a girl with her dog fell into the abyss together with water a long time ago. After two months, the water threw them out under the Bela Stena ...
From the confluence of the Zabava and Bukovska rivers, the river got its name Gradac. Thus, the river that springs below the mountain Povlen, after a few kilometers, sinks and erupts again near the village of Bogatić, above the famous Ćelije Monastery, near the Strong Spring. From there to Ćelije, Gradac flows through a winding gorge, makes a certain arch around the monastery and goes towards Valjevo, where it flows as the richest tributary into the famous river Kolubara. The river Gradac cut the gorge-canyon valley. With a length of 23 km and a depth of up to 200 meters, the Gradac canyon is the longest and most striking form of river erosion in the Valjevo karst. The canyon valley of Gradac consists of two parts. The upper part is called Suvaja, it is known as the periodic flow. The underground circulation takes place below the riverbed at an unknown depth, and is directed towards the Kolovrat spring, which is located on the right side of the riverbed downstream from Zelenac - the main spring. The lower part is downstream from the spring of Zelenac to Valjevo. From the source to the mouth in Kolubara Gradac has a length of 28 km and a total drop of 187 meters.
Izvor reke Gradac
Zabava je izvorišna reka Gradca, koja nastaje od nekoliko izvora u Kneževom polju ispod Malog Povlena (1347mnv), teče poljem kao potočić i ponire na kraju njega u krečnjačku jamu. Pojavljuje se ponovo na površini posle oko 200m ispod Bele stene, kao izvor Bele vode. Ime dobija tek kod Germanskih vodenica, ispod šume Jelje. Kako je reka dobila ime Zabava, niko ne zna. Na reci je nekada bilo 19 redovničkih vodenica i dosta pastrmke. Postoji i zaseok Zabava blizu reke. Zanimljivo je da je reč Z”abava” stara srpska reč i da je u dalekom srednjem veku značila ”Smetnja trgovačkom saobraćaju”.
Na mestu gde ponire bilo je jezerce i prema priči živela je aždaja u njemu, i povremeno izlazila ”da se šeta” po niskoj travi Kneževog polja. Ljudi i danas prenose svedočenje starih da je nekada davno u ponore zajedno sa vodom otišla neka devojčica sa svojim kučetom. Posle dva meseca voda ih je izbacila ispod Bele stene...
Od sastavaka Zabave i Bukovske reke tok dobija ime Gradac. Tako reka koja izvire ispod planine Povlen, posle nekoliko kilometara ponire i ponovo izbija kod sela Bogatića, poviše znamenitog manastira Ćelije, kod Jakog izvora. Odatle pa do Ćelija Gradac teče kroz krivudavu klisuru, pravi izvestan luk oko manastira i odlazi prema Valjevu, gde se uliva kao najbogatija vodom pritoka u slavnu reku Kolubaru. Reka Gradac usekla je klisurasto-kanjonsku dolinu. Dužinom od 23 km i dubinom do 200 metara, kanjon Gradca je najduži i najmarkantniji oblik rečne erozije u Valjevskom krasu. Kanjonska dolina Gradca se sastoji iz dva dela. Gornji deo se naziva Suvaja, poznat je kao periodski tok. Podzemna cirkulacija se odvija ispod rečnog korita na nepoznatoj dubini, i usmerena je prema vrelu Kolovrat koje se nalazi s desne strane korita nizvodno od Zelenaca - glavnog vrela. Donji deo je nizvodno od vrela Zelenca do Valjeva. Od izvora do ušća u Kolubaru Gradac ima dužinu 28 km i ukupan pad 187 metara.