In 1956, Dolomitas del Norte began mining the dolomite deposit located on Peña de Ranero. The extracted material (dolomite) was transported by aerial tramway to the Ambasaguas neighbourhood, where the unloading station and furnaces were located. There, it was processed for the manufacture of refractory tiles, which were essential for companies such as Altos Hornos de Bizkaia. This aerial tramway was the last one in Bizkaia. The route covered a distance of 2,888.4 m between the quarry and the factory, with a height difference of 281 m and a gradient of 9.8%. Along the route, the surrounding cable was supported by 27 metal trestles. The aerial tramway remained in operation until 1976, the year in which the quarry closed.

Due to its historical significance, all these facilities were declared a Cultural Asset with Monument status by the Basque Government in October 2002.

The Former Dolomite Works is an industrial heritage complex located in a rural and natural environment, where visits take place through original spaces linked to the former production activity. Access to the building is provided through a sliding door. The property is organised over several floors and retains original industrial construction elements, meaning that some areas may present limitations derived from its original configuration. In certain areas of the second floor, the clear passage width exceeds 0.94 metres, allowing relatively comfortable circulation in those sections. As accessibility conditions may vary depending on the areas open to visitors, it is recommended that each person, according to their specific accessibility needs, contact the managing entity in advance to obtain detailed information about available routes and support measures that may facilitate the visit.