Cologne is connected by bridges with the suburb of Deutz. Within the outer municipal boundary are included (besides Deutz) the suburbs of Bayenthal, Lindenthal, Ehrenfeld, Nippes, Sülz, Bickendorf, Niehl and Poll, protected by another widely extended circle of detached forts on both banks of the Rhine. Of the former city gates four have been retained, restored and converted into museums: the Severin gate, on the south, contains the geological section of the natural history museum; the Hahnen gate, on the west, is fitted as the historical and antiquarian museum of the city; and the Eigelstein gate, on the north, accommodates the zoological section of the natural history museum.
Cologne, with the tortuous, narrow and dark streets and lanes of the old inner town, is still regarded as one of the least attractive capital cities of Germany; but in modern times it has been greatly improved, and the evil smells which formerly characterized it have yielded to proper sanitary arrangements. The most important squares are the Domhof, the Heumarkt, Neumarkt, Alte Markt and Waidmarkt in the old inner, and the Hansa-platz in the new inner town. The long Hohe-strasse of the old town is the chief business street.
The cathedral or Dom, the principal edifice and chief object of interest in Cologne, is one of the finest and purest monuments of Gothic architecture in Europe (for plan, &c. see ARCHITECTURE: _Romanesque and Gothic in Germany_). It stands on the site of a cathedral begun about the beginning of the 9th century by Hildebold, metropolitan of Cologne, and finished under Willibert in 873. This structure was ruined by the Normans, was rebuilt, but in 1248 was almost wholly destroyed by fire. The foundation of the present cathedral was then laid by Conrad of Hochstaden (archbishop from 1238 to 1261). The original plan of the building has been attributed to Gerhard von Rile (d. c. 1295). In 1322 the new choir was consecrated, and the bones of the Three Kings were removed to it from the place they had occupied in the former cathedral. After Conrad's death the work of building advanced but slowly, and at the time of the Reformation it ceased entirely. In the early part of the 19th century the repairing of the cathedral was taken in hand, in 1842 the building of fresh portions necessary for the completion of the whole structure was begun, and on the 15th of October 1880 the edifice, finally finished, was opened in the presence of the emperor William I. and all the reigning German princes. The cathedral, which is in the form of a cross, has a length of 480, and a breadth of 282 ft.; the height of the central aisle is 154 ft.; that of each of the towers 511 ft. The heaviest of the seven bells (_Kaiserglocke_), cast in 1874 from the metal of French guns, weighs 543 cwt., and is the largest and heaviest bell that is rung. In the choir the heart of Marie de' Medici is buried; and in the adjoining side-chapels are monuments of the founder and other archbishops of Cologne, and the shrine of the Three Kings, which is adorned with gold and precious stones. The three kings of Cologne (Kaspar, Melchior and Balthazar) were supposed to be the three wise men who came from the East to pay adoration to the infant Christ; according to the legend, the emperor Frederick I. Barbarossa brought their bones from Milan in 1162, and had them buried in Cologne cathedral, and miraculous powers of healing were attributed to these relics. The very numerous and richly-coloured windows, presented at various times to the cathedral, add greatly to the imposing effect of the interior. The view of the cathedral has been much improved by a clearance of the old houses on the Domhof, including the archiepiscopal palace, but the new Hof, though flanked by many fine buildings, is displeasing owing to the intrusion of numerous modern palatial hotels and shops.