The River Vratna, a tributary of the Danube, is in the northeast of Serbia. Due to the unique interplay of geological features in its basin, a composite valley has arisen, with gorges and canyons carved out of the carbonate rock.
There are three large ‘gates’ (prerast) – natural stone bridges – over the Vratna, each of which has come about through a different process. They are a unique phenomenon, a specific phase in the evolution of tunnel caves and river meanders.
Suva Prerast came about where the Vratna disappears underground before a limestone ridge in a gooseneck meander. It is an imposing stone bridge 20 m high, 15 m wide and with a 34 m-wide arch.
Three kilometres downriver from the Suva Prerast is the Velika Prerast, a remnant of a former cave roof. It has a tunnel-shaped opening 45 m long, 26 m high and 22-33 m wide. There are a number of cave openings in the walls and roof of the bridge.
The Mala Prerast is just 100 m downriver from the Velika Prerast, at the very end of the canyon portion of the valley. From then on begins the wide expanse of the Vratna valley with its monastery complex. At the narrowest point of the exit, some 200 m upriver from the Vratna monastery, the slim arch of a natural stone bridge rises into the air, 34 m high, 33 m wide and 15 m thick.
The entire valley, which has resulted from the collapse of a cave roof through which the Vratna once flowed underground, and especially the attractive bridges – natural stone arches over the river – are exceptional examples of the action of river and karst processes in isolated limestone landscapes.
INFORMATIONJP “Srbijašume” Šumska uprava “Negotin” Generala Galebate 2,19300 Negotin tel: +381 (0)19 548-088 www.srbijasume.rs