The Vale do Aço Metropolitan Region (RMVA), commonly known as Vale do Aço, is a Brazilian metropolitan region located in the interior of the state of Minas Gerais, in the Southeast Region of Brazil. It was established by Complementary Law No. 51 on 30 December 1998 and officially designated as a metropolitan region on 12 January 2006. Situated in the Vale do Rio Doce, it comprises the cities of Coronel Fabriciano, Ipatinga, Santana do Paraíso, and Timóteo, along with a metropolitan belt consisting of 24 additional municipalities.

The region's exploration, which began in the 16th century but intensified in the 19th century, led to the emergence of the first urban centers, giving rise to several municipalities in the metropolitan belt. Due to the vast forests, the area was initially known as Vale Verde (Green Valley). The construction of the Vitória-Minas Railway between 1911 and 1929 facilitated colonization, but the establishment of Belgo-Mineira in Coronel Fabriciano in 1936 was pivotal in accelerating population growth, deforestation, and the development of housing, businesses, and streets. The establishment of Acesita (in Timóteo) and Usiminas (in Ipatinga) in the 1940s and 1950s, respectively, further provided basic infrastructure and recreational spaces, solidifying the integration of the current cities, which were under Coronel Fabriciano's jurisdiction until 1964.

Due to the economic significance of the steel industries, the region became known as Vale do Aço (Steel Valley). It gained international recognition for its major local companies, such as Aperam South America (formerly Acesita), Cenibra, and Usiminas. Despite its relatively recent settlement, it is one of the main urban hubs in the state's interior. According to statistics from the IBGE, the four main municipalities had a combined population of inhabitants in 2022. Attractions such as the Rio Doce State Park, the Ipanema Park, and Serra dos Cocais are also present in the RMVA, alongside handicrafts, rural congado groups, and cultural spaces such as the Aperam Acesita Foundation and the Usiminas Cultural Center.

History Early beginnings

Attempts to explore the Vale do Rio Doce for mineral wealth began in the 16th century but were unsuccessful. The expedition of Sebastião Fernandes Tourinho in 1573 navigated the Doce River and some of its tributaries, naming the region at the mouth of the Piracicaba River "Vale Verde" (Green Valley) due to its dense forest. In the 17th century, settlement and the opening of new trails in the Vale do Rio Doce were prohibited to prevent the smuggling of gold extracted from central Minas Gerais via the Doce River and its tributaries. In addition to the prohibition and dense forest, the rugged terrain and the fierceness of the Botocudo Indians also hindered colonization.

Settlement was permitted in 1755, following a decline in gold production in Minas Gerais. At that time, a road was opened linking Vila Rica (now Ouro Preto, then the capital of the Province of Minas Gerais) to Cuieté to transport gold extracted from the area of present-day Conselheiro Pena, which was depleted after 1780. As abundant gold was not found, the road was then used to connect Ouro Preto to a prison in Cuité, earning the name Estrada do Degredo. The existence of this road, which passed through the current municipalities of Dionísio, Marliéria, Pingo-d'Água, Entre Folhas, and Caratinga, among others in the metropolitan belt, later led to the emergence of the first settler communities in the interior of Vale Verde.

In 1800, the only reported settlement was in Antônio Dias, founded by the bandeirante Antônio Dias de Oliveira in 1706. However, in 1808, the publication of royal charters created government incentives for the colonization of the Vale do Rio Doce, authorizing land exploration and the extermination of indigenous peoples. A war against the Botocudo Indians ensued, involving settlers, immigrants, and soldiers. By 1831, a Royal Charter prohibited attacks on the Indians, but by then, they were nearly extinct. Small urban centers and occupations were reported throughout the 19th century, but they were insignificant compared to other regions of Minas Gerais, where economic activities were already well-established.

Settlement and urbanization

At the beginning of the 20th century, the so-called Vale Verde was still sparsely populated and almost entirely covered by virtually untouched Atlantic Forest. Settlement was encouraged by the construction of the Vitória-Minas Railway (EFVM) between 1911 and 1929. Upon reaching the current municipality of Belo Oriente in the late 1910s, railway construction was halted due to World War I, but it resumed in the following decade,Revista Caminhos Gerais, No. 35, p. 22. spurring the emergence of the first urban centers in Coronel Fabriciano and Timóteo, with the arrival of workers tasked with the construction, and later in Ipatinga. Shortly thereafter, the development of the MG-4 (now BR-381) through the region also contributed to the establishment of the urban perimeter.

In the 1930s, however, the establishment of the first industrial complexes became the primary factor in accelerating urban population growth, particularly with the Belgo-Mineira Steel Company, which sought to centralize wood extraction and charcoal production in Coronel Fabriciano, then a district of Antônio Dias, to supply its plants in João Monlevade. In the area of the former railway station in Coronel Fabriciano, Belgo-Mineira facilitated the construction of houses, businesses, and streets, encouraging population growth. The choice of this area for industrial production was enabled by the availability of transportation through the EFVM and the presence of abundant areas for raw material extraction. Acesita (now Aperam South America) and Usiminas, steel industry complexes established in 1944 and 1956, respectively, played a structural role in urban occupation and brought basic infrastructure such as healthcare facilities, schools, recreational spaces, transportation, and communications. With the arrival of these industries, the region ceased to be known as "Vale Verde" and was renamed "Vale do Aço".

Coronel Fabriciano, which became independent from Antônio Dias in 1948, was home to the industrial complexes of Acesita and Usiminas until 1964, when Timóteo and Ipatinga gained political emancipation, and the companies were transferred to these municipalities, respectively. In these cities, both companies were responsible for building numerous residential complexes to house employees, which later gave rise to the current neighborhoods. Even after losing the industrial complexes, Coronel Fabriciano continued to experience population growth due to the presence of the industries, but in a disorderly and unplanned manner, unlike the areas surrounding the plants in neighboring cities. The outskirts of Timóteo and Ipatinga, however, saw uncontrolled growth from the non-industrial population attracted by local progress. Urbanization intensified again in the 1970s with the establishment of Cenibra in the district of Perpétuo Socorro, in Belo Oriente. Like the industrial complexes in Timóteo and Ipatinga, it was positioned parallel to the BR-381, the Vitória-Minas Railway, and a water source (the Doce River in this case).

Metropolitan consolidation

In 1974, the first commission was formed to advocate for the recognition of Vale do Aço as an urban agglomeration, securing an audience with then-governor Rondon Pacheco in Belo Horizonte and obtaining funds for the project's implementation. That same year, the Association of Municipalities of the Vale do Aço Microregion (AMVA) was created. During the 1980s and 1990s, Santana do Paraíso, Belo Oriente, and part of Caratinga became part of the urban agglomeration.

Conversely, Coronel Fabriciano, Ipatinga, and Timóteo began to experience a reduction in growth rates due to the limited availability of areas for urban expansion. This slowdown had previously been observed only in cities within the current metropolitan belt, where rural exodus was significant during the second half of the 20th century, leading to population decline. Due to its proximity to Ipatinga's urban perimeter and easy access via the BR-458, the municipality of Santana do Paraíso, emancipated in 1992, experienced the highest population growth rates between the 1990s and 2000s.

The conurbation process known as Vale do Aço was recognized for its functional unity by Complementary Law No. 51 of 30 December 1998, integrating the municipalities of Coronel Fabriciano, Ipatinga, Santana do Paraíso, and Timóteo, along with 22 municipalities in the metropolitan belt. It was organized and officially designated as a metropolitan region by Complementary Law No. 90 of 12 January 2006. The Vale do Aço Metropolitan Agency, headquartered in Ipatinga, was established by Complementary Law No. 122 of 5 January 2012, when the municipalities of Bom Jesus do Galho and Caratinga were also included in the metropolitan belt.

In the early 2010s, under the effects of the financial crisis that began in 2008, there was a significant reduction in steel demand and subsequent production across Brazil, including Vale do Aço. This led to a considerable decline in the local industrial population due to job losses and investment cuts, with direct impacts on the service and commerce sectors due to the industrial crisis. In the early 2020s, despite stabilization and growth in the tertiary sector, the industry contributed less to new job creation.

Geography The Vale do Aço Metropolitan Region (RMVA) is located in the interior of Minas Gerais, east of the Belo Horizonte Metropolitan Region. The four main municipalities belong to the Intermediate and Immediate Geographic Regions of Ipatinga, according to the IBGE division in effect since 2017. The total area of the metropolitan core is km² according to the IBGE, of which km² (15.66% of the total) is urban.

Topography

Vale do Aço is situated within the interplateau depression of the Vale do Rio Doce, with its topography resulting from fluvial erosion acting on granite-gneiss rocks from the Precambrian period. The region features rocks from the gneissic-magmatic-metamorphic complex, including biotite-gneiss, granitic rocks, and granite-gneiss. As the name suggests, the region has characteristics of a valley, located in a low-lying area surrounded by elevated geological formations. Consequently, the topography is rugged, with its depression characterized by hills with moderate slopes intersected by fluvial plains and natural lakes.

The highest elevations in the metropolitan region are found in the northwest, in the territory of Coronel Fabriciano, where the Serra dos Cocais massifs are located. The average altitude ranges between 500 and 800 meters in this geological unit, which also limits urban expansion due to the terrain's layout. Conversely, the lowest elevations are found along the riverbanks, around which the industrial complexes of Usiminas and Aperam South America were established in Ipatinga and Timóteo, respectively. As a result, there is significant occupation and the emergence of neighborhoods, particularly low-income ones, in areas with steep slopes.

Hydrography