The São Domingos Mine is a deserted open-pit mine in São Domingos (Mértola), in the Alentejo region, Portugal. This site is one of the volcanogenic massive sulfide ore deposits in the Iberian Pyrite Belt, that extends from the southern Portugal into Spain.
The mining started many centuries ago, at the age of Romans, then had a brake until mid 19th century, as the international demand for copper grew during the Industrial Revolution. After the assignation of the mining concession in 1859 to the English mining company Mason and Barry, some important infrastructural work have been realized in the area, including an inland port and a railway. After a century of extractions, the mine eventually closed in 1966 due to mineral depletion.
Since closure the mine attracts tourists. Many old mine buildings and the open-cast pit remain abandoned, even though the old mining company headquarters has been converted into an hotel.
source: Sao Domingo page from Wikipedia