Dorsten, city, North Rhine–Westphalia Land (state), western Germany. It lies on the Lippe River and the Wesel-Datteln Canal. A village in Roman times, Dorsten was chartered by the archbishops of Cologne in 1251 and fortified in the 14th century. As a monastic centre it was a stronghold of the bishops. After 1802 it passed to the dukes of Arenberg, who held it as a fief of Prussia after 1815. The city developed industrially with the advent of the railway in 1899 and the opening of the first coal mine in 1911. The northernmost city of the Ruhr industrial region, it was badly damaged by bombing during World War II. Surviving buildings include a Franciscan monastery (1488), the old city hall (1597; now a local museum), a boys’ school (1642), and an Ursuline nunnery. The city’s economy was once based on coal, but the last mine has closed. Dorsten remains an important shopping and residential centre. The city was enlarged by nearly two-thirds in 1975, when it annexed Wolfing, Lembeck, and other neighbouring towns. Pop. (2003 est.) 80,397.