Algeria is the middle sector of the Atlas, of which Tunisia represents the eastern sector and Morocco the western sector. Therefore the general characteristics of its physical structure will be found under the heading atlas.
Algeria is among the African regions one of those with the best cartographic representations, thanks to the works carried out by the Service géographique de l’Armée. For all the northern maritime part, cultivable and colonized (called the Tell), there are maps at 1: 50,000, excellent, modern, superior to the old 1: 80,000 French. For the south, you have cards at 1: 200,000, which are quite good but will nevertheless be replaced by a collection now in preparation at 1: 100,000.
Algeria is a part of its own, as it is obviously a French colony, and a colony in the true sense of the word, a settlement colony, already a century old, where the number and influence of immigrants have now radically transformed the status quo.
One of its most obvious characteristics, the one that made the intensity of the colonial phenomenon possible, is the fragmentation of the country into clearly distinct provinces, in contrast with each other and also deeply hostile to each other. To give an idea of Algeria, therefore, it is certainly appropriate to proceed with its regional description.
The originality of Algeria, facing the two neighboring regions, Tunisia and Morocco, is constituted by the existence of an extensive area of high steppe plateaus, populated by nomads, which is interposed between the coastal area, narrow and elongated (the Tell), with Mediterranean climate, and the Sahara desert. This kind of structure, which has presided over the whole evolution of Algeria, must be examined first of all.
The Tell. – All that remains, apart from the steppe plateaus and the plateaus of Constantine, belongs to the Tell. What characterizes the Tell under the physical aspect is the fact that it has received from the Mediterranean rivers a normal modeling of erosion, which is in contrast to that of filling in closed basins, which dominates in the south. From the climatic point of view, it receives a sufficient amount of rain. It is the area of the sedentary peasants, the basis of Algerian economic power, the colonized region.
According to Indexdotcom, the Tell is also the coast, although it is a coast that exerts a minimal influence on the hinterland. It is cut sharply, and suddenly drops to great depths, without a continental base that offers a large area of exploitation to fishermen. And it is, moreover, a coast of continental emergence, unlike the Tunisian coast, where the submersion has given rise to a certain number of promontories (Bizerte). The Algerian coast has several large, very open, sloping bays of uniform type (Oran, Algiers, Bugia, Bona), in which the maritime city invariably rises along the western concavity, where it is sufficiently protected from the most violent storms, while remaining exposed to gusts of wind from the North and the NE. Mare saevum, litus importuosum, said Sallust. Indigenous maritime life has not developed at all. The sailors of the Maghreb have always been foreigners, from the time of the Carthaginians to that of the Turks of Algiers. French ports are artificial. This isolation from the sea certainly contributed to ensuring that, in the Mediterranean world, the Maghreb populations were constantly at the rear of the Berber civilization (probable etymology: the Latin word barbarians).
The Tell is a strip of land enclosed between the sea and the steppe, a strip a thousand kilometers long and just a hundred wide; and it was often observed how this unfavorable conformation hindered the formation of a state with a single center. It must also be added that this territory, which as a whole is very mountainous, is divided into distinctly distinct sectors.