The Television Tower Stuttgart. Archetype and symbol of modern mass communication

Description

The nominated property is the Stuttgart television tower, including the buildings at the base of the tower. The television tower stands in the Degerloch district of the state capital of Baden-Württemberg, above the Stuttgart valley. Measurements taken when constructing an efficient transmission network for the new medium of television at the beginning of the 1950s identified the Bopser mountain as a favourable location. Given the uneven topography of Stuttgart and its surroundings, an antenna height of around 200 metres was required.

The property nominated for inscription takes in all the grounds of the television tower as well as a part of Jahn Street with a unique view of the complete tower. The tower itself includes the underground foundations, the single-storey entrance/base building with its restaurant, the shaft of the tower, the tower cage with its upper and lower viewing platforms, the technical floor and restaurant, and the antenna. The upper viewing platform is located at a height of 150 m, and the top of the antenna reaches a height of just under 217 m.

The design and layout of the building were undertaken by Fritz Leonhardt (1910–1999), the static equilibrium calculations by Walter Pieckert (dates unknown), and the stress analysis by Karl Deininger

(1896–1956). Erwin Heinle (1917–2002) was responsible for the design and construction management of the ground floor, internal construction and the technical floor, and Herta-Maria Witzemann (1918–1999) for the interior design of the restaurants. The building was constructed for Süddeutsche Rundfunk (SDR).

Conceptually, the Stuttgart television tower was the first to combine its primary function as a transmitter mast with public accessibility and an elegant layout. In terms of statics, it is designed as a clamped, upwardly tapering tube. The combination of pressure-resistant concrete and tensile-strength steel makes the tower stable against winds from all directions. Wind tunnel tests have confirmed the round floor plan as ideal.

Foundations

A new type of foundation structure was developed to resist enormous wind forces. Two conical shells placed opposite one another distribute the loads from the tower in a ring shape beyond the tower core and tie into a circular, prestressed foundation plate with a diameter of 27 m. The foundations are therefore comparatively small. As a three-dimensional framework, the two conical shells stiffen the foundations, an unusual solution for the time. Leonhardt chose a radial reinforcement instead of a ring cable due to the construction site processes. The weight of the steel and concrete construction also has a stabilizing effect on the construction and favours the small foundations.

The foundation structure itself is completely underground, so that the tower virtually grows out of the ground and looks so slim – it was soon referred to as a concrete needle.

Tower shaft

The tower shaft is made of reinforced concrete and continued through the tower cage – as a cover for the lifts and as a platform for the antenna. The shaft was concreted in sections. The vertical reinforcement was placed in such a way that it overlaps the single sections. The reinforced concrete shaft tapers, following the model of the reinforced concrete chimneys of the 1930s in terms of diameter and wall strength, and thus fulfilling the statics requirements. Finally, in imitation of the ‘entasis’ of Greek columns, the conically tapering tower shaft was given a slight curve, which increases the contrast between the reinforced concrete tower and the cage, thus giving the tower a special elegance. Leonhardt calls this design principle ‘contrast proportion’.

At the foot of the tower, the external diameter of the walls amounts to 10.8 m with a wall thickness of 60 cm, while at the beginning of the tower cage it is only 5.04 m with a wall thickness of 18 cm. The thin wall diameter is guided by the space necessary for the lifts and the stairwells. A cross brace is inserted every 10m, which is combined with every second landing, similar to a bamboo tube.

In response to the continuously changing dimensions of the reinforced concrete tube, a climbing framework with a height of 2.5 m was added, which could be adapted to the respective cross-section using screw mechanisms. This new technology enabled, after an accustomization period, rapid construction of 2.5 m per work day. The rings corresponding to the transition between the concreting sections are clearly evident in early photos.

Tower cage

The tower cage starts at a height of 135 m and continues the round plan of the tower shaft. The form of the technical and catering floors recall the crow’s nest, or ‘mast cage’, of a sailing ship, which is why Leonhardt used the term ‘tower cage’. At first, only two floors were planned for the restaurant. However, with the limited space an additional floor for the kitchen was soon added. Still later, the idea arose to move the transmission technology from the base of the tower to the cage in order to save on expensive coaxial cable. From many alternative designs, Leonhardt chose a part-conical, part-cylindrical cage. The lower conical shell adjoins the shaft in a monolithic manner and supports the 18 reinforced concrete supports that bear the other floors of the cylindrical cage section. The smooth glass-and-aluminium façade is borrowed from aircraft construction and avoids contact points for wind forces. As a counterpoint to the verticality of the shaft, the façade is equipped with horizontal ribbon window bands, which also offer visitors an ideal all-round view.

Transmission antenna

The transmission antennas were attached to the 57m-long steel antenna support so that the tower reached an overall height of 211 m. Today’s antenna, which takes the tower to a height of just under 217 m, no longer serves for broadcasting television but rather for radio and police radio transmission. In addition, one of the 12 radio aerosol measuring stations for measuring radioactivity in Baden-Württemberg is installed here.

Entrance building

The single-floor entrance building with sloping roofs was built in a style typical of 1950s architecture and adjoins the tower shaft with a west and a north-east wing. It contains a restaurant, an entrance area with passage to the lifts, and operations rooms. The ground-floor building was repeatedly expanded in the following years – the restaurant in 1970 (office extension, Architekturbüro Erwin Heinle), 1978–79 and 1998 (extension of the seating area), the operations rooms in 1973 and 1982.

Justification of Outstanding Universal Value

The Stuttgart television tower created a novel architectural response to the inevitable visibility and technical requirements of a television broadcasting station. As an archetypal television tower, it is an outstanding international example of the architectural visualization of the television age from the second half of the twentieth century. The Stuttgart television tower combines for the first time a reinforced concrete shaft with a tower cage that includes a viewing platform and a restaurant. This concept, in combination with an elegant design and innovative construction solutions, made the tower not only the most famous landmark of the city of Stuttgart, but also established the image that is still associated with the archetypal television tower and the mass medium of television. The tower’s great success as a city landmark and identification point, and as a symbol and synonym for the city of Stuttgart, with supra- regional and worldwide recognition value, led numerous other big cities adapt this landmark.

Criterion (ii): The Stuttgart television tower is the first of its kind and marks the starting point of a global phenomenon in which television towers became the visible monuments of an invisible technical revolution. To this day, as the ‘mother’ of all television towers, it is associated with the beginning of nationwide television and the introduction of this important segment of 20th-century mass communication.

After the breakthrough of this technical innovation in the 1950s, the television medium developed rapidly during its first decades into a ubiquitous mass communication medium that took on a pervasive influence in our society. The occasion for the construction of the Stuttgart television tower was the expansion of the radio network within a chain of locations to ensure comprehensive network coverage of major German cities. In contrast to previous broadcasting stations and other television tower projects, Süddeutsche Rundfunk decided to trust Leonhardt’s vision and to give a new face to the still young television medium. The building thus took on a special role and established our working image of a modern television tower.

Criterion (iv): The Stuttgart television tower establishes the ‘building type television tower’ and is the prototype of a particular form of this type of building. Through the characteristics created by the Stuttgart tower, the television tower became one of the most easily recognizable building types of the twentieth century. With its architectural form and uses that go beyond pure functionality, it became the symbol for the mass medium of television. The tower serves as an outstanding illustration of this important moment in human history – the diffusion of television technology in the pre-digital age of mass communication.

The television tower as an established building type involves other qualities besides its original function as transmission station for television broadcasting. A key feature is the innovative shape and iconic silhouette of the Stuttgart tower, which give television towers a high recognition value. Furthermore, television towers of this type are in most cases open to the public and offer a centre of attraction for visitors. The characteristics of the Stuttgart tower, in terms of function, form and attraction, had a foundational influence on its innovative construction, which for the first time globally was built with a chimney-like reinforced concrete shaft and a viewing platform attached to a multi-storey cage. As a result of their required height, most television towers are landmarks that can be seen from afar.

The Stuttgart tower is a global model for this notion of the television tower building type. It combines for the first time various characteristics, which had their respective precursors but were brought together here in a prototype for the first time. As the archetype of all television towers, it is still the first outstanding testimony to the structural visualization of the television age, one of the most formative and significant moments in the human history of the twentieth century.

Statements of authenticity and/or integrity

Authenticity
As a functional building, the Stuttgart television tower, primarily and unchanged to this day, fulfils the function of a broadcasting station. In its spatial location as a widely visible landmark between city and nature, it has a great influence on the surrounding area and the city that lies at its feet. As the epitome of the television tower building type, it marks the beginning of the television age and has become a global model, in terms of construction and design, for many other television towers. The worldwide competition to create a widely visible television tower as a landmark, sparked by the Stuttgart tower, continues to this day.

The great authenticity of the nominated property is due to the fact that all the characteristics that make up the property have been preserved. The integrated design and construction are inscribed in the building work and nearly unalterable. Inside the building, the original surfaces of the shaft and the foundations, as well as the entire access core, are still authentic. As a result of structural damage, it was necessary to renew the outer surface of the shaft and the outer skin of the tower cage. The broadcast technology, which has been continuously used and adapted since the building’s opening, as well as the (re)building phases in the catering floors, are part of the history of changes in the tower. In this way, the television tower is an authentic witness to the inevitable development, as well as the longstanding constants, in the history of broadcast technology and of stations for analogue terrestrial television.

Intactness
The boundaries of the nominated property within the site delimitation of the television tower includes all structures and components relevant to the construction and development of the television tower. In this way the property fully expresses all the features and processes that manifest its outstanding universal value.

All the important features of the property remain in near-unaltered form and design, and document the continuity of use of the broadcasting station and the catering and tourist operations. The original functions have thus remained largely intact and legible.

The property’s elegant architectural design and its recognizability as the model for the television tower building type remain just as intact. The spatial impact of the television tower landmark and its identity- creating effect are undiminished.

The Stuttgart television tower is not endangered by the negative effects of building projects and/or neglect, and has a high degree of structural, functional and visual integrity.

Comparison with other similar properties

As the archetypal television tower, the Stuttgart tower serves as a global model of the structural manifestation of modern mass communication. Consistent with the deficit of world heritage sites relevant to mass communication identified in the Getty Conservation Institute’s study The Twentieth- Century Historic Thematic Framework (2020), there are currently no world heritage sites that reference the medium of television. The Grimeton Radio Station in Sweden, which began operation in 1924, is considered an outstanding example of the development of telecommunications. It is indeed a forerunner in terms of mass communication, but not comparable to the Stuttgart television tower because of its traditional architecture and lack of planned accessibility for the public.

There are currently only two towers on the UNESCO tentative list: the Ještěd television tower in the Czech Republic (construction period 1966–73, listed 2007), which can be seen in the broadest sense as a further development of the Stuttgart tower, and the Abraj Al-Kuwait Towers in Kuwait (construction period 1971–76, listed 2014), which is not comparable with the Stuttgart tower in formal, functional and constructive terms. There is no comparable building on the world heritage list itself.

In order to identify possible comparable buildings, five attributes were identified that characterize the Stuttgart television tower and thus also represent the fundamental characteristics of the TV tower building type: broadcasting function, innovative form, attraction, pioneering construction, and landmark (see criteria ii and iv). These attributes for comparative analysis express the outstanding universal value that is being proposed for the property.

Various building types, such as 19th-century viewing towers, radio broadcasting stations and reinforced concrete chimneys, served as inspiration for the Stuttgart tower and partly connect some of the five attributes. The Stuttgart television tower, however, was the first of its kind that brought together these various qualities in an innovative way so that a new building type was created. Since then, the Stuttgart television tower has served as a role model worldwide and established the image that is still globally associated with the television tower type and the mass medium of television.