Rhine-Ruhr in the context of "Metropolitan region"

A metropolitan area or metro is a region consisting of a densely populated urban agglomeration and its surrounding territories which share industries, commercial areas, transport network, infrastructure and housing. A metropolitan area usually comprises multiple principal cities, jurisdictions and municipalities: neighborhoods, townships, boroughs, cities, towns, exurbs, suburbs, counties, districts and even states and nations in areas like the eurodistricts. As social, economic and political institutions have changed, metropolitan areas have become key economic and political regions.

In the United States, metropolitan areas are delineated around the core of a core based statistical area, which is defined as an urban area and includes central and outlying counties. In other countries metropolitan areas are sometimes anchored by one central city such as the Paris metropolitan area (Paris). In other cases, metropolitan areas contain multiple centers of equal or close to equal importance, especially in the United States; for example, the Dallas–Fort Worth metropolitan area has eight principal cities. The Islamabad–Rawalpindi metropolitan area in Pakistan, the Rhine-Ruhr in Germany, and the Randstad in The Netherlands are other examples.

North Rhine-Westphalia or North-Rhine/Westphalia, commonly shortened to NRW, is a state (Land) in Western Germany. With more than 18 million inhabitants, it is the most populous state in Germany. Apart from the city-states (Berlin, Hamburg and Bremen), it is also the most densely populated state in Germany. Covering an area of 34,084 km (13,160 sq mi), it is the fourth-largest German state by size.

North Rhine-Westphalia features 30 of the 81 German municipalities with over 100,000 inhabitants, including Cologne (over 1 million), the state capital Düsseldorf (630,000), Dortmund and Essen (about 590,000 inhabitants each) and other cities predominantly located in the Rhine-Ruhr metropolitan area, the largest urban area in Germany and the fourth-largest on the European continent. The location of the Rhine-Ruhr at the heart of the European Blue Banana makes it well connected to other major European cities and metropolitan areas like the Randstad, the Flemish Diamond and the Frankfurt Rhine-Main Region.

Duisburg (German: [ˈdyːsbʊʁk] ; Low German: Duisborg, pronounced [ˈdʏsbɔɐ̯χ]) is a major city in the western part of Germany, located in the state of North Rhine-Westphalia. With around half a million inhabitants, it is one of the largest cities in the Ruhr urban area and part of the larger Rhine-Ruhr metropolitan region, one of the biggest population centers in Europe. Duisburg is situated at the confluence of the Ruhr and the Rhine, a geographic position that has historically made it an important center of trade, industry, and transportation. Administratively, Duisburg forms an independent city (kreisfreie Stadt).

The city is known for hosting the world's largest inland port, the Port of Duisburg [de], which plays a key role in European logistics and international trade. The port's facilities are directly linked to major motorways, rail networks, and the Rhine waterway, connecting Duisburg to the North Sea and beyond. Today, Duisburg is a hub for the steel, chemical, and logistics industries, and it has also become an important node in trade relations with China, being a key terminus for freight trains on the Chongqing–Xinjiang–Europe railway.

Gelsenkirchen (/ˌɡɛlzənˈkɪərxən/, /ˈɡɛlzənkɪərxən/; 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 [de].

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 [de]. The city bore the name Gelsenkirchen-Buer, until it was renamed Gelsenkirchen in 1930. The city remained a center of coal mining and oil refining during the Nazi era, so was often a target of Allied bombing raids during World War II: nevertheless, over a third of the city's buildings date from before 1949. 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.

Bochum (/ˈboʊxʊm/, BOHKH-uum; US: /-əm/ -⁠əm; German: [ˈboːxʊm] ; Westphalian: Baukem) is a city in North Rhine-Westphalia. With a population of 372,348 (April 2023), it is the sixth-largest city (after Cologne, Düsseldorf, Dortmund, Essen and Duisburg) in North Rhine-Westphalia, the most populous German federal state, and the 16th-largest city in Germany. On the Ruhr Heights (Ruhrhöhen) hill chain, between the rivers Ruhr to the south and Emscher to the north (tributaries of the Rhine), it is the second largest city of Westphalia after Dortmund, and the fourth largest city of the Ruhr after Dortmund, Essen and Duisburg. It lies at the centre of the Ruhr, Germany's largest urban area, in the Rhine-Ruhr Metropolitan Region, the second biggest metropolitan region by GDP in the European Union, and belongs to the region of Arnsberg. There are nine institutions of higher education in the city, most notably the Ruhr University Bochum (Ruhr-Universität Bochum), one of the ten largest universities in Germany, and the Bochum University of Applied Sciences (Hochschule Bochum).

Dortmund (German: [ˈdɔʁtmʊnt] ; Westphalian: Düörpm [ˈdyːœɐ̯pm̩]; Latin: Tremonia) is the third-largest city in North Rhine-Westphalia, after Cologne and Düsseldorf, and the ninth-largest city in Germany. With a population of 614,495 inhabitants, it is the largest city (by area and population) of the Ruhr as well as the largest city of Westphalia. It lies on the Emscher and Ruhr rivers (tributaries of the Rhine) in the Rhine-Ruhr Metropolitan Region, the second biggest metropolitan region by GDP in the European Union, and is considered the administrative, commercial, and cultural centre of the eastern Ruhr. Dortmund is the second-largest city in the Low German dialect area, after Hamburg.

Founded around 882, Dortmund became an Imperial Free City. Throughout the 13th to 14th centuries, it was the "chief city" of the Rhine, Westphalia, and the Netherlands Circle of the Hanseatic League. During the Thirty Years' War, the city was destroyed and decreased in significance until the onset of industrialisation. The city then became one of Germany's most important coal, steel, and beer centres; as a consequence, it was one of the most heavily bombed cities in Germany during World War II. The devastating bombing raids of 12 March 1945 destroyed 98% of the buildings in the inner city. Involving more than 1,110 aircraft, the raids were the largest targeting a single city during World War II. Today, around 30% of the city’s buildings date from before the war.

Düsseldorf (German: [ˈdʏsl̩dɔʁf] ) is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in the state after Cologne and the sixth-largest city in Germany, with a 2024 population of 618,685. Most of Düsseldorf lies on the right bank of the Rhine, and the city has grown together with Neuss, Ratingen, Meerbusch, Erkrath and Monheim. Düsseldorf is the central city of Rhine-Ruhr, the second biggest metropolitan region by GDP in the European Union, that stretches from Bonn via Cologne and Düsseldorf to the Ruhr.

Düsseldorf began as a small settlement at the mouth of the Düssel River, gaining city rights in 1288 after the Battle of Worringen. In the Late Middle Ages and Renaissance, it grew into a regional political and cultural centre under the Dukes of Berg and later as the capital of the United Duchies of Jülich-Cleves-Berg. The 17th and 18th centuries saw flourishing arts and architecture, with Düsseldorf becoming known for its court culture and early art academy. During the Napoleonic era, it was briefly part of the Grand Duchy of Berg before coming under Prussian control in 1815, where it industrialised rapidly in the 19th century. During the 20th century, Düsseldorf developed into one of Germany’s most important centres for administration, business, and culture. In 1946, it became the capital of the newly created state of North Rhine-Westphalia, strengthening its political role.

Leverkusen (German: [ˈleːvɐˌkuːzn̩] ) is a city in North Rhine-Westphalia, Germany, on the eastern bank of the Rhine. To the south, Leverkusen borders the city of Cologne, and to the north the state capital, Düsseldorf. The city is part of the Rhine-Ruhr Metropolitan Region, one of Europe's largest urban areas.

With about 163,000 inhabitants, Leverkusen is one of the state's smaller cities. The city is known for the pharmaceutical company Bayer and its sports club Bayer Leverkusen.

Bonn (German pronunciation: [bɔn] ) is a federal city in the German state of North Rhine-Westphalia, located on the banks of the Rhine. With a population exceeding 300,000, it lies about 24 km (15 mi) south-southeast of Cologne, in the southernmost part of the Rhine-Ruhr region.

Bonn served as the capital of West Germany from 1949 until 1990 and was the seat of government for reunified Germany until 1999, when the government relocated to Berlin. The city holds historical significance as the birthplace of Germany's current constitution, the Basic Law.