The Engineer - Jan 1960: The Dortmund Tower

The Dortmund Tower offered the finest perspective to onlookers of a botanical event in Germany.

In Germany, a federal horticultural show called the Bundesgartenschau takes place every two years. The show lasts for a few months and is hosted by a different city each time. Its current motto is 'we make cities greener'.

In 1959, the city of Dortmund was bestowed with a great honor. In celebration, a broadcasting and observation tower, commonly known as the Dortmund Tower or Florianturm, was constructed as a highlight for the summertime festivity.

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The tower, created by architect Will Schwarz, was the world's pioneer with a rotating eatery housed within it. It also earned a distinction for being the heightiest structure in Germany temporarily, standing at 220m, including antennas. If you frequently visit Frankfurt, you won't be shocked to learn that the current record-holder for this feat is the Commerzbank Tower, towering at 259m, a title it held for six years from 1997 to 2003, as the tallest building in Europe.

Frankfurt is considered the financial center of Germany and has a high concentration of tall buildings. However, the trend of constructing large, stand-alone structures dates back to the period of rapid construction after the Second World War in various parts of Europe. The Engineer, in its January 1, 1960 publication, reported on this phenomenon.

After the completion of the Stuttgart television tower, it seems like there's a competitive vibe among the major cities in Germany and nearby nations. They're all trying to construct similar towers,” according to our journalist. Some instances of this competition include the Rotterdam Euromast and Dortmund's observation and telecommunications tower.

The Dortmund Tower was constructed from May 22, 1958 to April 30, 1959. It consisted of a reinforced concrete cylinder that stood 173.45 meters tall and narrowed from an 11.74-meter diameter at ground level to 5.50 meters at a height of 133.2 meters.

The base goes down to a depth of negative eight times ten meters and comprises a round concrete base that measures 25 meters across. The thickness at the center of the base is 2.5 meters.

According to The Engineer, the tower has two different balcony sections. The lower one is situated between 133.2m and 144.7m levels and is larger than the upper one which is located between 151.8m to 155.5m levels. The lower platform has a diameter of approximately 14.74m and includes two inner levels. The upper level, which is at the height of 137.6m, can accommodate up to 100 people in a restaurant setting, while the lower level placed at 133.2m is designated for a kitchen area and offices. This section of the tower is supported by a cantilevered ring. The roof of the lower balcony acts as a viewing platform that has the capacity to hold 200 people at any given time.

Our journalist also noticed that despite the primary framework being made of concrete, the restaurant's flooring and its transparent exterior are constructed with steel. This steel structure is created with rollers that assist in its gradual rotation through the utilization of an electric drive.

According to our journalist, the arrangement of the restaurant was chosen based on several factors. The most significant factor was to ensure that every table has a view of the entire panorama. Additionally, it was important to maintain a consistent temperature inside the restaurant, which can be challenging on sunny days as one side of the restaurant can get excessively hot and in winter, the shady side may lose heat through windows. The rotating floor and windows eliminate these problems. They help reduce the adverse effects caused by sunlight and radiation and maintain an even temperature inside the restaurant.

Another advantage is that the glass is less likely to warp due to heat buildup. The equipment includes an electric motor with 8 horsepower, which can be adjusted to produce speeds of 2 to 6 rotations per hour by using a variable gear mechanism.

According to our journalist, there is some technology set up on the top balcony of the building that is 151.7m high. This gear helps to transmit signals in a particular direction. On the remaining 17.2m concrete section above that, certain types of antennas have been placed. There are also two poles for broadcasting television signals that are on top of the concrete tower. Both poles are stacked on top of each other, and they are 46.15m tall when combined.

Visitors can now reach the observation deck quickly thanks to the high-speed elevators in the Dortmund Tower. The website known as "Big Beautiful Buildings" has reported that the tower's height decreased to 208m due to some changes made in its antennae.

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