The Zagros Mountains (In Persian:رشته‌کوه‌های زاگرس) make up Iran's second largest mountain range. They have a length of 1500 kilometres from western Iran, from Kurdistan at the border with Iraq to the southern parts of the Persian Gulf. The range ends at the Straits of Hormuz.

The mountains are divided into many parallel sub-ranges (up to 10, or 250 km), and have the same age and orogenesis as the Alps. The country's main oilfields lie in its western central foothills. The highest point of this range is Zard Kuh (4548 metres). The southern ranges of the Fars Province have lower summits (up to 4000 m) and some limestone rocks show a lot of fossils. Joining a special surveyor group, fossile snails of 2 kilograms can be found at altitudes of 3000 metres. It is hard to imagine that these summits were part of the deep ocean some 50 million years ago.

The Kuhrud Mountains are a parallel range at a distance of approx. 300 km to the east. Between these impressive mountain chains lives a dense population: the valleys are quite high with a temperate climate, and the rivers, which flow into salt lakes, create a good environment for agriculture and commerce.