Demographic developments in Tanzania are not well known. In the last years of the twentieth century the population increased at a rate of 2.5% (1993-98), not excessively high compared to the birth rate (41 ‰ in 1997), and this because a large part of the population still lives in very backward conditions and mortality is very high. According to 800zipcodes, more than half of the population is under the age of 20; the average density is 43 residents / km², but the distribution is very irregular. As a general phenomenon there is the tendency, however already sensitive in the past, of a migratory flow towards the coastal strip, richer in activities. But, if we exclude the area of Dar es Salaam, this is not the most densely populated part of the country; in the region of Kilimanjaro, rainy and fertile, there are approx. 90 residents / km², which is one of the highest values in Tanzania at the level of administrative regions. Generally sparsely populated, on the other hand, is the whole central section of the other lands, where there is a typically African settlement of villages that gravitate around the centers located on the main roads, market centers and, today, clinics, government offices, shops, etc. Villages are also found on the coast, where there is also the scattered house or family settlement; this also applies to Zanzibar. The houses along the coast have a square plan, while in the Savannah areas they generally assume circular shapes; the Masai finally live in theirs manyatta, settlements that have a duration of 6-7 years, characterized by the central enclosure for livestock. The country is innervated on a network of urban or commercial centers which, in its structure, was essentially outlined in the colonial age, although the coastal sites pre-existed. The urban population, however, in 2005 was only 24.2%. Until the last century Zanzibar was the largest city on the coasts of the Indian Ocean: an active commercial center, managed by the Arabs, it had a number of residents not much lower than it is today. Its urbanism was, as it still is at the beginning of the 2000s, that of Arab cities, with narrow streets full of shops, a port frequented by numerous sailing ships and boats. Other pre-existing centers of urban dimensions were Bagamoyo, now decayed, and Tanga, lively port with good development as a coastal terminus for the railway leading to the populous area dominated by Kilimanjaro.
Keystone of the entire territorial organization of Tanzania, main port and airport, seat of industries and commercial activities, is Dar es Salaam, capital of the country until the related administrative and political functions were assumed by Dodoma, located right in the heart of Tanzania, in an essentially rural and typically African area. Even at the beginning of the twentieth century Dar es Salaam, the “haven of peace”, was a modest center, previously founded by the sultan of Zanzibar; then it became the main port of the country, also serving eastern Zaire, the outlet of the whole plateau to which it was connected with the railway line for Tanganyika, to which must be added the very important Tan-Zam, the railway that connects the Tanzania to Zambia and thanks to which the latter, without direct access to the sea, has its own maritime opening in Dar es Salaam. The construction of the railways – all lines of penetration – is responsible for the urban network of Tanzania which, in addition to the aforementioned coastal centers, includes some cities hinged precisely on the railway axes. On the railway from Dar es Salaam to Lake Tanganyika (with arrival point in Kigoma) there are Morogoro, Dodoma and Tabora, the central node of the plateau, from where a line branches off to Lake Victoria, thus linking the former capital to Mwanza. major port center on the shores of the great lake, while the Tan-Zam touches Mbeya, the main center of the Kipengere mountains area. The railway from Tanga to the Kilimanjaro area has finally enhanced Arusha, a market in a populous agricultural region, also frequented by the Masai, and Moshi, at the foot of Kilimanjaro, which has become a renowned tourist resort. from where a line branches off to Lake Victoria, thus linking the former capital to Mwanza, the largest port center on the shores of the great lake, while the Tan-Zam touches Mbeya, the main center of the Kipengere mountain area. The railway from Tanga to the Kilimanjaro area has finally enhanced Arusha, a market in a populous agricultural region, also frequented by the Masai, and Moshi, at the foot of Kilimanjaro, which has become a renowned tourist resort. from where a line branches off to Lake Victoria, thus linking the former capital to Mwanza, the largest port center on the shores of the great lake, while the Tan-Zam touches Mbeya, the main center of the Kipengere mountain area. The railway from Tanga to the Kilimanjaro area has finally enhanced Arusha, a market in a populous agricultural region, also frequented by the Masai, and Moshi, at the foot of Kilimanjaro, which has become a renowned tourist resort.
