It is composed of six islands two of which are populated: Gharbi (or little Kerkennah) and Chergui (or Large Kerkennah). They are connected between them by a roadway (El Kantara) existing as of the Roman epoch. There are also 4 uninhabited islands named Gremdi, Sefnou, Roumadia and ar Remadia.
The effective population size is 14,400 inhabitants but during summer there are over 120,000 people living in the 18 different villages. There are just one road, which crosses the archipelago between Sidi Youssef (at the western end) and El Attaya (at the end). The perimeter of the archipelago exceeds 160 kilometers.