Lying on the Ruhr and the Rhine-Herne Canal, Essen has been one of Germany's main industrial centers since the 19th century. Despite the war damage, many monuments from the 10th and 11th centuries, during the Ottonian rule, have been preserved here.
The most important monuments of the city are a complex of late Romanesque and Gothic buildings from the period of Otto's rule. It consists of a former female monastery and the cathedral of St. Kosma and Damian with the tomb crypt of Ottons, a statue of the Golden Madonna from the end of the 10th century and a treasury in which liturgical items from the 10th and 11th century are stored. Within the Old Town, the late Gothic churches of St. Gertrude and St. John the Baptist.
The second group of Essen monuments is associated with its industrial development, which began in the 18th century. These include primarily villas and palaces belonging to industrialists, including the Krupp family, as well as the buildings of former factories. In 2001, the industrial complex of the Zollverein mine and coking plant was included on the UNESCO list as a unique example of the history of technology and industrial architecture. The factory is also on the European Industrial Heritage Trail.
