It runs for over 100 kilometres (62 mi) south from Matmata, curving gently to the east to sink beneath the dunes of the Grand Erg Oriental near Tataouine.

There is little vegetation, consisting of lucerne, thorn bushes, and the occasional palm tree, giving the landscape a lunar appearance.

Jebel Dahar has been inhabited for thousands of years by various Berber tribes, who farm the mountain slopes on terraced fields to retain runoff water from the rare rainfall.

Sometimes further rooms are created which are reached by means of a rope and steps cut in the wall; these are used for storage and traditionally for the first week after a couple's marriage.

A tunnel is dug from the inside to form an exit, with a slight downwards incline so that any rain water can run out of the dwelling.

The exit door is usually decorated with traditional symbols such as the hand of Fatima or a fish, and is often concealed between rocks and bushes.

The cave dwellings are well adapted to the climate, remaining cool in summer and retaining warmth in winter, and it is disputed how far they should be regarded as defensive as opposed to purely practical.

The majority, especially younger people, have moved into the new blocks of flats in urban areas, which are sometimes unpleasantly cold in winter and require air conditioning in summer, but offer electric stoves, washing machines, and other modern comforts.

In Jebel Dahar, they were often built on steep crags for additional defence; those on the plain are believed to have been constructed in relatively peaceful periods.