The Reales Fábricas was a brass works that operated for 233 years. It was created in 1773 with patronage from King Charles III by the Viennese engineer Juan Jorge Graubner, who had come to Madrid aged 22. Graubner developed an existing mine for zinc ore and created a water-powered factory. The operation spread over a distance of 10km and was served by aqueducts and reservoirs. It made a variety of brass artefacts as well as parts for armaments and ships. A new community was created by skilled workers who arrived from other countries. The museum is based in the brass-works buildings. The equipment preserved includes furnaces, hand-tools and machine tools for fabricating brass artefacts, polishing tools, laboratory equipment and hydroelectric turbines. Many examples of brass and bronze products are on display, such as plaques and sculptures, candlesticks and doorknockers, together with patterns and moulds for casting. Models show the buildings and their operation.