Note: The western German city of Leverkusen is located on the Rhine river at the mouth of the Wupper, north of Köln. The city was formed by the union of Schlesbusch, Rheindorf, Steinbüchel and Wiesdorf in 1930. It is noted as center of Bayer Works, which produces chemicals, pharmaceuticals and photographic film. The city's industries also produce textiles and iron products. Its primary historic and cultural site is Morsbroich Castle, which contains an art museum and a theater for plays and concerts. The population estimate for 2004 was 160,000.