Castres (; Castras in the Languedocian dialect of Occitan) is the sole subprefecture of the Tarn department in the Occitanie region in Southern France. It lies in the former province of Languedoc, although not in the former region of Languedoc-Roussillon. In 2018, the commune had a population of 41,795. Castres is the fourth-largest industrial centre of the predominantly rural former Midi-Pyrénées region after Toulouse, Tarbes and Albi, as well as the largest in the part of Languedoc lying between Toulouse and Montpellier. It is noted for being the birthplace of the famous socialist leader Jean Jaurès (1859–1914) and home to the important Goya Museum of Spanish painting. Demographics In 1831, the population of Castres was 12,032, making it the largest town of the department of Tarn. One of the few industrial towns in the region of Albigeois, the population of the commune proper grew to 19,483 in 1901, and 34,126 by 1954. However, with the decline of its industries, population growth diminished. Albi surpassed Castres as the most populous metropolitan area of Tarn. The population of Castres reached its peak in 1975, after that it has been decreasing slowly. Castres is the centre of a functional urban area with 104,695 inhabitants (2019). Geography Castres is located at an altitude of above sea level. It is located south-southeast of Albi, the préfecture (capital) of Tarn, and east of Toulouse, the capital of Occitania. Castres is intersected from north to south by the rivers Agout and Durenque. The Thoré forms most of the commune's south-eastern border, then flows into the Agout, which forms part of its western border. Administration Between 1790 and 1797 Castres was the prefecture of Tarn. Since 2001, the mayor of Castres has been Pascal Bugis (right, member of UMP), who defeated the then socialist mayor in the 2001 election after a campaign focused on the bad records of the socialist mayor on fighting crime, and the high level of insecurity in the town. Castres has teamed up with the nearby town of Mazamet ( southeast of Castres) and the independent suburbs and villages in between to create the communauté d'agglomération de Castres Mazamet, which was established in December 1999. The communauté d'agglomération groups 14 independent communes (including Castres and Mazamet), with a total population of 78,101 inhabitants (2018), 54% of these living in the commune of Castres proper, 13% in the commune of Mazamet, and the rest in