El Serrallo, San Martín del Rey Aurelio
In 1892, the limited partnership Minas de La Encarnada was set up, under the business name of Vigil Escalera y Compañía. Its purpose was the extraction of coal and all kinds of minerals and the main exploitation core was located in La Hueria de Carrocera valley, in La Encarná, which gives its name to the company.
In the articles of association of the company, a concession entitled Sultana appears. Although far from La Encarnada, it seems to be located in Sotrondio. The curious name of this mine, like Generala's one, or the nearby toponyms of El Serrallo or Tetuán, has been linked to the African wars. This was very common from the end of the 19th century onwards.
La Sultana is a good example of the use of a material that was not widely used in the façade of the adits: brick. Here, it is used in the arch and in the wall, using ashlar for the arch startup, the capstone and the keystone. The keystone bears the date 1918, although it must come from a remodeling and a consolidation of a much older adit.
At the beginning of the 2000s, the San Martín del Rey Aurelio Town Council intervened in these adits with little success and less expertise, although the positive aspects were their signposting and maintenance, which has not been continued.