Krupp City is a nickname for the German city of Essen, which has five letters. It is named after the Krupp family, who were prominent industrialists in the 19th and 20th centuries. The city is known for its steel production, and the Krupp family's company, Krupp AG, was one of the largest steel producers in Europe. The city is also home to several museums and cultural attractions, making it a popular tourist destination.