Riotinto-Nerva mining basin

The basin holds an extensive historical and industrial heritage as a result of the activities that took place during the Contemporary Age, especially those related to the British period.

[1] The Riotinto-Nerva mining basin is located in the northeastern part of the province of Huelva, within the historical region of eastern Andévalo, at 418 meters above sea level.

The mining area is framed within the low mountain landscape that predominates in the Andévalo, with a relief of relatively smooth terrain - between 700 and 500 meters.

The isotopic analysis at Riotinto have revealed that there was already considerable activity since at least 366 BC,[7] while the oldest remains of mining operations and human settlements have been found in the area of Filón Norte.

The Romans carried out the extraction labors by means of a network of underground galleries and complex systems of hydropowered scoopwheels to move the water inside.

[12] The Romans erected numerous buildings in the area to support mining and metallurgical activities, such as furnaces and foundries, as well as roads to facilitate the transit of goods.

The current Corta del Lago housed the main Roman settlement in the area, which classical sources identify as Urion or Urium.

[14] The metallurgical work carried out in Roman times left a large quantity of slag and considerably altered the physiognomy of the territory.

The American mines were of greater interest to the authorities, in contrast to those of Huelva, which were considered to be exhausted after their intense exploitation in Roman times.

Influenced by the industrial revolution that was taking place, the Riotinto mines began to face problems due to the lack of infrastructure and technology, which prevented an adequate exploitation.

[21] However, in the middle of the 19th century, the poor financial situation of the Spanish State made it impossible for it to make optimal use of its mining properties.

[22] By the middle of the 19th century, the Riotinto mines aroused the interest of international capital, in a context in which the industrial take-off that some European countries were experiencing had increased the need for access to new sources of raw materials.

After the triumph of the revolution of 1868 and the political change that followed, in March 1870 the minister Laureano Figuerola presented a project for the sale of the Riotinto mines to the Cortes.

In 1873, the House of Rothschild acquired the ownership of the deposits from the government of the First Republic, which was transferred months later to the newly created Rio Tinto Company Limited (RTC), of British origin.

Mining work was initially concentrated in "La Mina" deposit (or "Filón Sur"),[25] although by 1881, the operations had already been expanded to other parts of the area.

[30] The British maintained the traditional system of galleries, although by the end of the 19th century they began to implement open-pit mining - the so-called "cortas" - that allowed for a greater volume of mineral extraction.

[Note 3] The expansion of mining and metallurgical activities meant the need for a greater number of workers, which would eventually lead to an exponential increase in the population of the area.

[33] Working conditions in the mining basin were "extraordinarily harsh" and on numerous occasions led to labor disputes that pitted workers against RTC's British management.

The reprisals imposed by the RTC after this strike led to the dismantling of the trade union movement in the area for many years, and it was not until the times of the Second Republic when it was reorganized.

[38] In addition, the mining and industrial facilities were outdated, with a business model focused on the export of minerals; all this would lead to a new line of action.

[41] The rest of the deposits remained under the management of CEMRT, whose expansion plans led to the creation of the Unión Explosivos Río Tinto (ERT) group in 1970.

A large portion of this pyrites was destined to the factories that were built in the chemical park of Huelva,[43] created in 1964 to promote the economic development of the area.

[Note 4] In the 1980s, the persistently poor economic performance led to major labor disputes and the progressive halting of operations on the copper line.

[44] Up to the 1990s, the company Río Tinto Minera (RTM) carried out the main activity in the basin, but the crisis of the industry would eventually lead to the shutdown of most of the facilities in the area.

[46] Parallel to this process, during the 1980s, various proposals were made that focused on the conservation of the environmental and patrimonial heritage of the mining basin, faced with the threat of its disappearance.

[47] Major work in this regard has been performed by the Rio Tinto Foundation, an institution that has contributed to the recovery of numerous industrial heritage and the establishment of the tourist mining train.

[51] With the expansion of activities throughout the basin, the RTC provided electricity as a source of energy to its industrial facilities, the homes of the British personnel, workers' villages, etc.

[55] The commissioning of the Campofrío reservoir provisionally solved the shortage problems and provided drinking water to the municipalities of the mining basin.

[63] This 21-kilometer-long route connected the Peña del Hierro deposit with the railway line of the Cala mines, thus facilitating the exit of the ore to a pier on the Guadalquivir river.