​OPLADEN, a town of Germany, in the Prussian Rhine Province, 10 m. N.E. from Cologne by the railway to Elberfeld and at the junction of lines to Speldorf and Bonn. Pop. (1905) 6338. It has an Evangelical and a Roman Catholic church. It has dyeing works, and manufactures of dynamite, indigo products and railway plant. Before passing to Prussia, Opladen belonged to the duchy of Berg.