Portugal, a small country, has a wide variety of landforms, climatic conditions, and soils. The topography changes from area to area, but the most notable differences are those between the north and the south; the Rio Tejo forms a convenient dividing line between the hilly to mountainous regions of the north and the great rolling plains of the south. Within these two major geographic regions there are subdivisions that further reflect the vast differences in the country. The names of the six provinces that existed from medieval times until the nineteenth century are used to designate the various geographic regions. Three of these regions -- the Minho, Trás-os-Montes, and Beira -- lie completely north of the Tejo. Three-quarters of Estremadura is also north of the river. The remainder of Estremadura, the Alentejo, and the Algarve fie south of the river.
The Minho occupies the northwest corner of the country between the Rio Minho in the north and the Rio Douro in the south. The Minho's western boundary is the Atlantic Ocean. The coastal plain in that part of the country generally does not exceed five miles in width and by the mid-1970s had not attained the economic importance of the southern coast. From the narrow coastal strip the land rises steeply to levels 1,000 to 2,000 feet above sea level. The Minho's eastern boundary is delimited by a range of mountains, forming a ring that separates it from Trás-os-Montes (literally, beyond the mountains). When the old provinces were subdivided in 1833, the Minho was divided into the districts of Viana do Castelo, Braga, and Porto. The overall favorable climate and abundant rainfall support the most intensive agriculture in the country, and the Minho is very densely populated despite heavy emigration. The emigration has resulted from the fragmenting of family farms through inheritance over several generations until the small plots have become unprofitable and too small for further subdivision. Many young men have chosen to emigrate rather than remain landless in their homeland.
Trás-os-Montes, the northeasternmost area of Portugal, encompassing the districts of Vila Real and Bragança, is bounded on the north and cast by Spain, on the south by the Rio Douro, and on the west by the mountains that separate it from the Minho. The mountains cause the clouds moving toward Trás-os-Montes to precipitate, and as a result this region is and and parched in comparison with the lush green of the Minho. On the western side of the mountains the average annual rainfall approaches 100 inches, but on the Trás-os-Montes side the average is less than twenty inches. The dryness and the composition of the soils have made this a region of cereal cultivation, principally rye, and animal grazing. The famous port wine area of the Rio Douro is situated on the terraced slopes of that river along the southern boundary of Trás-os-Montes. The terraces on which the vines are grown were hand cut into the slopes down to the Douro valley by generations of Portuguese peasants. Trás-os-Montes is sparsely populated, particularly as compared with the Minho.
The Beira region is much larger than the two northern regions, stretching from the Spanish border in the east to the Atlantic coast in the west and from the Rio Douro in the north as far south as the Rio Tejo. When the provinces were subdivided, Beira was made into five districts: Aveiro, Coimbra, Viseu, Guarda, and Castelo Branco. Aveiro and Coimbra districts are commonly referred to as Beira Litoral (Coastal Beira), Viseu and Guarda as Beira Alta (Upper Beira), and Castelo Branco as Beira Baixa (Lower Beira) -- the 1933 province names.
Beira Litoral and Estremadura to the south as far as Lisbon are unique among the landforms of the Iberian Peninsula in that the area is younger geologically and contains sandstone, limestone, and volcanic rock rather than the granite and schist that are predominant in other areas. The Beira coastal plain, which extends inland up to thirty miles from the ocean as opposed to the very narrow coastal strip of the Minho, contains salt marshes and alluvial deposits and stretches of sand dunes sometimes two to five miles in width. Around the lagoon known as the Ria de Aveiro there is a fertile region of land reclaimed from the sea. The lower course of the Rio Mondego crosses a fertile area of Beira Litoral that, taken as a whole, is one of the more fertile regions of the country and features rice, corn, grapes, and forest products among its varied produce. Fishing is also important to the economy of the coastal region, which supports a much larger population than the interior.
Beira Alta contains the Serra da Estrêla, Portugal's major mountain range (the highest peak is 6,532 feet). The Serra da Estrêla, which stretches across the country for about seventy-five miles and averages about thirty miles in width, forms a barrier in the center of Portugal. Communication can only be effected easily along the coast or on the relatively lower land east of Guarda. The more humid western half of Beira Alta is densely populated, and its terraced slopes are noted for a variety of crops, including corn, cabbage, and grapes. To the east the population is less dense and, where cultivation is possible, there are more cereal crops. Summer pastures on the Serra da Estrêla have long been important to the widespread sheep raising in the area.
Beira Baixa is a dry and windswept region that is similar to Trásos-Montes in its economy and population density. This area is an extension of the Spanish plateau and rises to an average height of about 2,000 feet. The economy is mixed -- stockraising and cereal-crop cultivation combined with some mining and manufacturing. The southern portion of Beira Baixa is a transitional area that begins to resemble the rolling hills of the Alentejo and is covered with cork oak plantations and olive groves.
Estremadura, part of Portugal's unique coastal region, includes the Tejo estuary, the capital city of Lisbon, and the important Tejo valley area known as Ribatejo. The old province was divided into the districts of Leiria, Santarúm, Lisbon, and Setúbal. Estremadura's fertile soils and moderate climate support an intensive agriculture and a dense population. The region is known for its grapes, and its wines are considered among Portuguese to be second only to those of the Douro. The Setúbal area is also noted for its orange groves, and in the northern Ribatejo cattle breeding is an important sector of the economy. Lisbon, situated on the Tejo esturary, is the country's political, cultural, and economic center.
The Alentejo (literally, land across the Tejo) is a vast area of gently rolling hills generally rising to about 600 feet but occasionally reaching between 900 and 1,500 feet. Although the Alentejo is remarkably and monotonously similar in its topographic appearance, it is usually divided into two subregions, Alto Alentejo (Upper Alentejo) encompassing the districts of Portalegre and Evora and Baixo Alentejo (Lower Alentejo) being conterminous with Beja, the largest district in the country. Until the revolution of 1974 the Alentejo was the land of latifundios or estates of up to 1,000 acres in size. They were vast in comparison with the family farms of the Minho and were often owned by absentee landlords. Wheat and rye are grown on the plains of the Alentejo, but the area is also known for its large ranges of cork oak and its olive groves. Cattle raising and pig raising are also important to the economy. The Alentejo is one of the driest regions in the country, and it also experiences rather wide extremes of temperature, particularly in the east along the Spanish border. The kind of farming, the climate, and the bleakness of the land have all served to hold down the population and, particularly when compared with most regions north of the Tejo, the Alentejo is very sparsely populated.
The Algarve is a distinct region, not only geographically but also culturally because of a persistent Moorish influence. This was the last area of the country to be taken from the Moors, and its towns and buildings as well as the speech of its inhabitants all reveal evidences of its Moorish background. The Algarve is separated from the Alentejo by two mountain ranges, the Serra de Monchique in the west and the Serra do Caldeirão in the east; these mountains also serve to differentiate the hilly interior of the province from its low coastal plain. Much of the mountainous area is covered by scrub growth and poor soils and is very sparsely populated, whereas the coastal lands are fertile and densely settled. Stock grazing and grain production are important in the dry areas of the western Algarve, but to the south corn is widespread in cultivable areas, and tree crops become predominant. Cork oak and olives are grown, but the climate is particularly favorable for the growing of fruit trees; and the sunshine, meager rainfall, and warm winters of the coastal plain have aided the production of almonds, carobs, figs, oranges, and pomegranates. The proximity to the sea has ensured that many inhabitants of the Algarve earn their livings from fishing, and there are many engaged in agriculture who also work part time in the fishing industry. When the six provinces were subdivided into districts in 1833, the Algarve's boundaries were left intact, and the province became the district of Faro.
There are several zones of intense seismic activity as well as major geological faults in Portugal. The largest zones are concentrated in the Algarve, the greater Lisbon area, and the Rio Tejo estuary as far as Benavente. Smaller zones fan out from Porto along the rim of the mountainous amphitheater of the Minho region. There are other, scattered zones in Portugal. Large faults crisscross the Minho region, and larger ones extend into Spain along the north side of the Serra da Estrêla. Faults in Estremadura reach into the Lisbon area. In southern Portugal there is a triangular fault along the eastern edge of the Serra de Grándola (near the coast, west of the Rio Sado) and another extending from Beja in a southwestern direction.
The disastrous earthquake of November 1, 1755, killed an estimated 20,000 people in the Lisbon area and caused extensive damage in the lower portion of the old city. In the south Setúbal, Lagos, Portimão, and Faro suffered considerable damage as well. Lisbon was subsequently rebuilt, and architecture designed to resist further earth tremors was employed in the lower portion of the city.