43°2′36″N 23°21′10″E / 43.04333°N 23.35278°E
The Iskăr Gorge is a 70 km (43 mi) gorge passing through the Balkan Mountains (Stara Planina) in Bulgaria. It is the chief pass through the Balkans, which otherwise cross northern Bulgaria in a solid line.[1] The pass connects the capital of Sofia with other major cities in the country, such as Mezdra. There is a road and a railway through the pass, following the course of the Iskar River.[1]
The canyon walls are made of limestone and sandstone, which was carved down by the Iskar over thousands of years, resulting in rugged crags and towers throughout.[1] At one point, the walls are nearly 300 metres (980 ft) tall.