Coat of arms of Gelsenkirchen, Germany

Gelsenkirchen (UK: /ˈɡɛlzənkɪərxən/, US: /ˌɡɛlzənˈkɪərxən/, German: [ˌɡɛlzn̩ˈkɪʁçn̩] ; Westphalian: Gelsenkiärken) is the 25th-most populous city of Germany and the 11th-most populous in the state of North Rhine-Westphalia with 262,528 (2016) inhabitants. On the Emscher River (a tributary of the Rhine), it lies at the centre of the Ruhr area, the largest urban area of Germany, of which it is the fifth-largest city after Dortmund, Essen, Duisburg and Bochum. The Ruhr is located in the Rhine-Ruhr metropolitan region, the second-biggest metropolitan region by GDP in the European Union. Gelsenkirchen is the fifth-largest city of Westphalia after Dortmund, Bochum, Bielefeld and Münster, and it is one of the southernmost cities in the Low German dialect area. The city is home to the football club Schalke 04, which is named after Gelsenkirchen-Schalke. The club's current stadium Veltins-Arena, however, is located in Gelsenkirchen-Erle. Gelsenkirchen was first documented in 1150, but it remained a tiny village until the 19th century, when the Industrial Revolution led to the economic and population growth of the region. In 1840, when the mining of coal began, 6,000 inhabitants lived in Gelsenkirchen; by 1900 the population had increased to 138,000. In the early 20th century, Gelsenkirchen was the most important coalmining town in Europe. It was called the "city of a thousand fires" for the flames of mine gases flaring at night. In 1928, Gelsenkirchen was merged with the adjoining cities of Buer and Gelsenkirchen-Horst. The city bore the name Gelsenkirchen-Buer, until it was renamed Gelsenkirchen in 1930. There are no longer coalmines in and around Gelsenkirchen; the city is searching for a new economic basis, having been afflicted for decades with one of the country's highest unemployment rates.