Djerdap National Park is located in the north-east Serbia, on the border with Romania and encompasses a part of the Djerdap gorge area (Iron Gate) in the middle flow of the Danube. The area has been under protection since 1974 covering the area of 63,768 ha.

The most distinctive feature of the relief and the distinguishing mark of the national park is a grandiose Djerdap gorge, the longest and the largest breakthrough in Europe. The Djerdap gorge consists of four smaller gorges and three alternating basins at the stretch of 100 km.

Veliki Kazan is the most beautiful gorge among the small ones. In this part of its flow, the mighty Danube is captured between the steep, often vertical, up to several hundred meters high cliffs above the river, the width of which does not exceed 170 m. This is the deepest point of the Danube. The depth of 90 meters, measured in one of the giant pools, is one of the greatest depths in the world. The beauty of Veliki Kazan leaves incredible memories in the minds of its visitors, regardless whether you observe it from the river or from the edge of a cliff above the river. This is where it becomes obvious how Djerdap (Iron Gate) got its name.

The south background of the gorge has been segmented by the erosion of the larger number of the right tributaries of the Danube. The Boljetin River stands out by its attractive and dynamic morphology. The canyon is important as an object of geological heritage because the complete geological history of this part of Europe from Paleozoic to Cenozoic is reflected in it. This geological profile is one of the most renowned ones in Serbia, due to its beauty.

Owing to the great length and depth, different exposures, most diverse forms of relief and sheltered habitats with specific microclimates, the Djerdap gorge is one of the most important refugium of ancient flora and fauna of Europe.