To their south lies the Saharan desert.
The Saharan Atlas is essentially one chain, though known under different names: Jebel K'sur and Jebel Amur on the west, and Jebel Aures in the east.
The importance of the town as a trans-Saharan trade centre has greatly declined since the suppression of slave-trading by the French.
This depression is the termination of what is in all probability the bed of one of the dried-up Saharan rivers.
The Great, or Saharan Atlas contains some of the highest points in the country.
Above the sea, looking out on the Saharan desert, and 200 m.
The northern portion, from about 16° N., is practically the south-eastern continuation of the Saharan desert; the southern region is fertile, abundantly watered, and in places densely forested.
The area of the lake is shrinking owing to the progressive desiccation of the country, Saharan climate and conditions replacing those of the Sudan.
The southern or main range of the Eastern division is known by the French as the Saharan Atlas.
The central part, the Zab Mountains, is of lower elevation, the Saharan Atlas reaching its culminating point, Jebel Shellia (7611 ft.
In the Saharan Atlas the passes leading to or from the desert are numerous, and in most instances easy.
By an exception rare in Saharan settlements, there are no defensive works save the fort containing the government offices, which the French have built on the south side of the town.
Gabes lies at the head of the shat country of Tunisia and is intimately connected with the scheme of Commandant Roudaire to create a Saharan sea by making a channel from the Mediterranean to these shats (large salt lakes below the level of the sea).
The range of the Saharan Atlas of Algeria divides (roughly speaking) into two at the Tunisian frontier.
To some extent it may be said that true North Africa lies to the north of the Jerid country, which, besides its Saharan, Arabian and Persian affinities, has a touch about it of real Africa, some such touch as may be observed in the valley of the Jordan.
On the whole its character is less Saharan than that of parts of Algeria, for the influences of the desert do not penetrate so far north in Tunisia as they do in Algeria.
The present writer, riding up to these frontier mountains from the thoroughly Saharan country round Gafsa, found himself surrounded by a flora very reminiscent of Switzerland or England.
On the other hand, the flora of the shat region, of the south-eastern littoral, and of the Kerkena islands opposite Sfax, is thoroughly Saharan, with a dash, as it were, in places of an African element.
South of that point the Saharan frontiers of Algeria, Tunisia and Tripoli remained undefined.
The Little Atlas, otherwise the Tell or Maritime Atlas, lies between the sea and the Saharan Atlas, and is composed of many distinct ranges, generally of no great elevation and connected by numerous transverse chains forming extensive table-lands and elevated valleys.
(For the climate of the Saharan region see Sahara.) Throughout Algeria, especially in the summer, there is a great difference between day and night temperature, notably in the inland districts.
In the Saharan oases the characteristic tree is the date palm - " the king of the desert."
There are complete postal and telegraphic facilities in all parts of the colony save the Saharan Territories, and cable communication with France.
By decree of the 14th of August 1905, the frontier between Saharan territory dependent on Algeria and that attached to French West Africa was laid down.
The Algerian Sahara was divided into four territories, officially named Tuggurt, Ghardaia, Ain Sefra and the Saharan Oases (Tuat, Gurara and Tidikelt).
Besides these isolated posts Spain holds Rio de Oro, a stretch of the Saharan coast, and its hinterland lying between Morocco and French West Africa; the Muni River Settlements or Spanish Guinea, situated between French Congo and the German colony of Cameroon; Fernando P0, Annobon, Corisco and other islands in the Gulf of Guinea.
The Cretaceous seas appear to have extended into the central Saharan regions, for fossils of this age have been discovered in the interior.
Near Bilma is a small circular oasis, kept green by a fine spring, but immediately to the south begins the most dreary part of the Saharan desert, over which the caravans travel for fifteen days without discovering the slightest trace of vegetable life.
The name Biskra applies to a union of five or six villages of the usual Saharan type, scattered through an oasis 3 m.
ADRAR (Berber for "uplands"), the name of various districts of the Saharan desert, Northern Africa.
Along the northern border of the protectorate this has resulted in the encroachment of the Saharan desert over once fertile districts.
There are in addition a territorial army reserve and a special body of troops, largely Arab, for the defence of the Saharan territory.