Ruhr-Al City is a term used to refer to the German city of Essen, which has five letters. Essen is located in the Ruhr region of Germany and is the ninth largest city in the country. It is known for its industrial heritage, having been an important coal mining and steel production center during the 19th and 20th centuries. Today, Essen is a major cultural and economic hub in the region, with a vibrant art and music scene, as well as a number of universities and research institutions.