The Danube Boilers are made up of a Large and a Small Boilers, these represent a narrow sector of the Danube Canyon.
In this area, Danube crosses the narrowest (230 m) and the grandest area of the Danube Canyon, Boilers Danube, having a 9 km lenght.
The Danube is bordered by vertical walls and cliffs. Maximum depth is 75 m.
Large Boilers have a 5 km length. Are located between massifs Ciucaru Mare (Romania) and Veliki Strbac (Serbia).
Small Boilers have a 4 km length , are located between massifs Ciucaru Mare (Romania) and Mali Strbac (Serbia).