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THE MINES: human transformation of the landscapeBack

From remote times, man has extracted vast amounts of minerals that have helped towards survival and to undertake large works. Part of the territory of Bizkaia has been modified due to the mines that crossed its geography. The most important iron vein, even when compared to others beyond our boundaries, was that of the Valley of Somorrostro, whose exploitation caused a deep alteration of the scenery.


The Valley of Somorrostro historically comprises the municipalities of Muskiz, Abanto y Ciérvana/Abanto Zierbena, Zierbena, Santurtzi, Ortuella, Valley of Trápaga/Trapagaran and Sestao, although the councils of Galdames and Sopuerta have to be included in the mining area designated as such. Known from remote times, as vouched for by the Roman remains found therein, it was cited by Plinius in the year 67, when he visited the area as procurator of Hispania. In his work, Naturalis Historiae, when referring to the mines, he mentions “… a rough and high iron mountain, a beautiful sight …” For centuries, iron of the highest quality in Europe was extracted, apart from the fact that it was an easy mine to exploit as its orebearing beds were located on the surface.

Air ironworks remains have been found along the Oiola river; this was the method used up to the Middle Ages, and hydraulic ironworks replaced these from the 13th century onwards (ironworks of El Pobal). Located on the low banks of the river, the ironworks had a building which received water through a canal with a cascade that turned the mill, transmitting the force to the bellows that stoked up the fire and the large drop hammers used for forging the iron. The first ironworks were located on the mountainside, where there were plenty of trees that provided the necessary fuel.

Important mining exploitation did not commence until the end of the 19th century; the inhabitants of Galdames, Muskiz, Barakaldo, Trapagaran, Ortuella and Sopuerta, combined their agricultural tasks with those of extraction and transport of the mineral to the ports. After the Second Carlist War, the State Law of Mines was implanted in Bizkaia, which fostered the concentration and exhaustive exploitation of the deposits. This, jointly with the Bessemer converter, led to the important mining and iron and steel industry of Bizkaia. The good quality of the mineral, its easy exploitation and its closeness to the coast were the determining factors that attracted the large foreign companies to the mines of Somorrostro.


The open-air exploitation was undertaken with drillholes, manually perforating the beds with bore-bits and hammers, albeit during the first stages of mining, picks and hoes were used. Steam drill hammers and electric hammers were first used in 1903, and were finally replaced by excavators in modern times. Dynamite was used for blasting, and “sabolite” was used during the 20s. After the blast, the mineral was cut up into pieces, and then it was selected, loaded and transported. The first step consisted of taking the mineral to the railway, so that it could be transported to the port, or to the blast furnaces. There were several methods for transporting the mineral from the exploitations: headways, slopes through which the wagons moved impelled by a tractor cable (cable system), or through a chain line (floating chain system); or aerial trams, which consisted of a series of posts that held the cables that supported the buckets. After this, the mineral was transported through the vast mining railway networks. The only remaining coast loader can still be seen in Pobeña, this being the location from which the mineral was exported to various European countries (see the recreational area of Siete Robles).

Galleries had to be opened when the mines ran out of mineral, and the material that had been previously discarded in dumps was also used. This “blonde” mineral was mixed with clay and had to be washed down to eliminate the same. To this avail, mineral washeries were built, water canals and decantation reservoirs (see recreational area Parque Las Balsas de la Baluga), which provoked a new change in the landscape, with “lakes” and very flat and muddy areas due to the decantation of the water after washing the mineral. Exploitation of carbonates commenced as from 1881, and these were burnt in kilns (see recreational areas of Santa Ana de La Baluga and Siete Robles), to be subsequently turned into oxides.

The first blast furnace, Santa Ana de Bolueta, was set up in 1848, using charcoal as fuel. “Altos Hornos” and the Iron and Steel Factory of Bilbao were set up in 1882, which subsequently became “Altos Hornos de Vizcaya”, the flagship of the industry of Bizkaia for decades.

After the First World War, the rhythm of exploitation of the mines declined during the thirties, as reserves were depleted. The last mining exploitation closed down in 1993, the Mina Bodovalle de Gallarta, with a gallery that went into the sea some 400 m. This large-scale mining exploitation entailed the creation of an important infrastructure, which left a deep mark on the environment, with huge craters and cracks that alternate with artificial reservoirs, dumps, etc.

The exploitation system required a great number of workers and this demand was mainly covered with immigrants from the Basque Country and from the north of Spain in general, with the logical setting up of mining districts. The main group settled in La Arboleda, exploitation that was set up in 1877, involving various thousands of inhabitants. The highest peak recorded around twenty thousand workers, and the extremely hard working conditions and overcrowding led to accidents, infections and epidemics. The cholera epidemic that commenced on the 5th of October of 1885 in all the mining area, was the most outstanding, decimating the population in Bizkaia. The first mining hospital was created in 1880 in Gallarta, and a branch hospital soon followed in Matamoros-Burtzako (Zugaztieta/La Arboleda) and another one in El Cerco (Galdames).

As from 1886, miners associated in trade union movements which turned the area into a workers’ bastion, to demand improvements in their working conditions, such as an 8-hour shift, stipulating a minimum salary and legislation to protect handicapped people.

The mining museum is located in Gallarta, containing photographs and materials from that period; the Interpretation Centre of Peñas Negras also has graphic documentation on the subject.


This route, of great ecological and scenery interest, will lead us, through old mining routes, to the impressive cave of Urallaga, which houses the hermitage of La Magdalena inside the same. Throughout the route, we will see the ruins of mining villages, such as El Pico and Urallaga, which in old times witnessed an incessant hubbub of people and the racket made by the roar of the machines that robbed the earth of its precious materials, now forgotten even by the elderly.

The Atxuriaga park, located on the country road that links the districts of San Pedro (Galdames) and el Arenao (next to Sopuerta) indicates the beginning of this outing. There is a dirt track that commences at the end of the parking area, which was the old track of the mining railway of Galdames. This railway began to operate in 1878, run by the company Bilbao River, leaving from Galdames to Sestao and running for 23 kilometres, linking with a collateral line that went to Sopuerta and another to Castro Urdiales.

After 5 minutes’ walk, we abandon this track and continue through the path that goes to the right. Vegetation mainly comprises willows and eye-catching plumes, this being a very humid area settled on the remains of the Berango Mine. The track becomes steep and rises in wide zigzags shaded by oak and pine trees, until it reaches, after thirty minutes’ walk, an open area next to a fountain and the ruins of a house of the vanished quarters of El Pico. From this point, one can see Galdames, Mt. Ubieta in front, and to the right, the fertile lowland of Sopuerta. The track leads to a stream bed over which there is a mineral dump and this is a recommended itinerary due to the spectacular landscape it offers.

Continuing on this track, and always ascending, it surrounds the massive void left by the Mine Rita, an open-air exploitation. Under a eucalyptus plantation, the track takes a turn, crossing a copse with common oaks, “marojo” oaks, hazelnut trees and chestnuts, contemplating the deep crater of the mine from another perspective. The ruins of the village of Urallaga can be accessed through a rockier terrain; this is located in a beautiful spot, protected by ash trees and surrounded by green pastures that have been parcelled out. This human settlement was so important during the golden era of mining, that the corn exchange of Galdames was set up in this area.

To the right, a grassy route under the oaks goes down crossing the stream bed, feasting our eyes with the spectacular spot of the cave of Urallaga. This outing will take us approximately one hour and fifteen minutes since we left the Atxuriaga Park. A slope by the old wall of the dam goes into the ample entrance to the cave. Underneath the same, the plentiful waters of the Eskatxabel stream gush from a gallery.

The humble hermitage of La Magdalena is located in the very entrance of the Urallaga cave, next to an abyss. Here, a very popular pilgrimage takes place, mainly in La Arboleda on the 22nd of July, where numerous people arrive on horseback.

From Urallaga, a path rises to the area of El Sauco, and numerous outings can be taken from this spot.