Cologne Cathedral - Vierungsturm panoramic view
The building of a spire above the Vierung section (centrepoint of cross) constituted one of the most challenging new construction tasks presented by completion work on the cathedral in the 19th century.As work progressed on the cathedral, a lively discussion ensued as to the precise design of the Vierungsturm. In 1821, Sulpiz Boisserée unveiled his vision of a complete cathedral, envisaging a massive stone spire structure. However, ultimately, a much slimmer and lighter spire was constructed from iron, based on a drawing concept from Ernst Friedrich Zwirner, not least because this design imposed a substantially lower mechanical loading on the eastern Vierung buttresses constructed back in the 13th century.
The building of this Vierungsturm was awarded to Kölnische Maschinenbau AG in Bayenthal, the winner of the public invitation to tender. In just one year, between October 1859 and September 1860, the profile sections, some of which were made at the iron foundry operated by mining and steelworks specialist Phönix AG based in Eschweiler-Aue, were supplied and installed on site.
The once majestic neo-Gothic decorative zinc castings on the Vierungsturm with their ornate detailing, filigree spires and intricate arches, were almost completely destroyed in the wake of bomb damage during World War II. The modern reconstruction with its smooth lead cladding was created between 1961 and 1973, based on the designs of Willy Weyres. Since this time, eight gigantic figures of angels created by the sculptor Erlefried Hoppe decorate the buttresses of the Freigeschoss section.
From the lofty 70 metre viewing platform, whose ramparts still feature the original zinc castings of the 19th century, you can enjoy a unique 360° panoramic view of cathedral and city. There is also a small iron table here, covered with a protective lead cladding, constituting the trigonometric centrepoint for European cartographic triangulation measurements in 1867.
Ever since 1803, Cologne Cathedral has been used for extensive cartographic and other measurements, without doubt as a result of its dominant location above the Rhine plain. During the period of French occupation, this triangulation point was located on the lantern of the baroque figure standing astride the nave roof. However, when this feature was demolished in 1811, the triangulation point was relocated to the giant Firstkreuz cross on the nave roof. During the Prussian cartographic survey of Rhine Province and Westphalia in 1824, all coordinates were uniformly referenced to Cologne Cathedral as their datum point. An observation spire erected on the spire at the southern end in 1860/61 but never completed had to give way to further extension of the main spires. As a consequence, this iron observation table with central measuring point was located on the Vierungsturm, completed just a few years previously. This fixed point retained binding character until 1891, at which point it ceded this status to the tip of the Vierungsturm.
To this day, Cologne Cathedral literally plays a pivotal role, with the Vierungsturm as its centrepoint, in all regional cartographic mapping exercises.
