The technology for extracting sugar from beet was developed by Prussian chemist Andreas Markgraff in 1747. The first sugar factory in Silesia was opened in 1797 by his pupil Franz Achard, and the industry was supported by the government in Prussia in the nineteenth century. The factory at Oldisleben in Thuringia, stone buildings with internal structures supported by cast-iron columns, was established by a co-operative in 1872, alongside an earlier sugar factory of the 1830s. It began production on 27 February 1873 and has a 41.5 m brick chimney. The factory’s last campaign ended on 18 December 1990 when it was the last in Europe using technology that dates from the 1970s. It was subsequently classified as a protected monument. The plant includes six boilers installed between 1889 and 1925, a diffusion battery of 1906, a lime plant of 1898 and a 300 hp steam engine of 1915 that can still be worked. Visitors can be shown round the plant on request, and are shown a 20-minute film followed by a tour of the extensive buildings.