Cologne headquarters and workshops in Cologne. Other large companies based in Cologne include the REWE Group, TÜV Rheinland, Deutz AG and a number of Kölsch breweries. Cologne has the country's highest density of pubs per capita. The largest three Kölsch breweries are Reissdorf, Gaffel, and Früh. Historically, Cologne has always been an important trade city, with land, air, and sea connections. The city has five Rhine ports, the second largest inland port in Germany and one of the largest in Europe. Cologne-Bonn Airport is the second largest freight terminal in Germany. Today, the Cologne trade fair ("Koelnmesse") ranks as a major
Electorate of Cologne confused with the Roman Catholic Archdiocese of Cologne, which was larger and included suffragant bishoprics such as Liège and Münster over which the Elector-Archbishop exercised only spiritual authority (see map below). Cologne was the ancient Roman city of Colonia Agrippina in the province of Germania Inferior, and has been a bishop's see since Roman times. In 953, the archbishops of Cologne first gained noteworthy secular power, when Bishop Bruno was appointed as duke by his brother Emperor Otto I. To weaken the secular nobility, who threatened his power, Otto endowed Bruno and his successors in the bishop's see with the