The World Clock at Alexanderplatz

The World Clock at Alexanderplatz in Berlin, also known as the Urania World Clock, has been a popular meeting point and impressive technical masterpiece since its inauguration in 1969. This ten-meter-high clock displays the time in 146 cities worldwide and has been under monument protection since 2015. Designed by industrial designer Erich John, it represents the GDR Modernism and is equipped with a rotating cylinder representing the time zones of the Earth. Driven by a modified Trabant gearbox, the clock was restored after the reunification and extensively renovated in 1997. Today, it is a cultural symbol of Berlin, a tourist attraction, and an integral part of city tours.

World Clock at Alexanderplatz in Berlin

The World Clock at Alexanderplatz in Berlin, also known as the Urania World Clock, is a prominent clock installation that has served as a popular meeting point for Berliners and tourists since its inauguration in 1969. The ten-meter-high clock displays the time in 146 cities worldwide and has been under monument protection since July 2015. It was created as part of the socialist redesign of Alexanderplatz and reflects GDR Modernism. It is located not far from the Berlin TV Tower.

The World Clock was designed by industrial designer Erich John and consists of a rotating cylinder with 24 facets representing the time zones of the Earth. Originally, the idea for the clock came from a found Urania column. The clock is powered by a modified Trabant gearbox and displays the current times in different time zones. After the reunification, the clock was restored, correcting erroneous city-to-time-zone mappings and adding new cities.

The clock was extensively renovated in 1997 and has since been under monument protection in an updated form. In 2018, Erich John transferred the marketing rights to a Berlin-based start-up and was awarded the Federal Cross of Merit in 2021 for his creation. The World Clock is not only a technical masterpiece but also a cultural symbol of Berlin and an integral part of city tours, appreciated by tourists and locals alike.

Structure, Technology, and Operation of the World Clock

Above a wind rose mosaic set into the ground, the World Clock rises, consisting of a 2.7-meter-high column and a three-part cylinder with a diameter of 1.5 meters. The cylinder has 24 sides, each representing one of the 24 main time zones of the Earth. The entire construction is ten meters high and weighs 16 tons. The names of important cities are engraved on the aluminum plates of the cylinder, and a rotating hour ring displays the time in the time zones. Above the clock, a simplified representation of the solar system rotates once per minute.

The clock’s technology is housed in a 5 by 5-meter room, 1.90 meters high, two meters below the square. The drive is provided by a modified Trabant engine and a ball bearing from the Rothe Erde company.

During the 1997 renovation, aurotech GmbH took over the technical part. A new geared motor rotates the hour ring five percent faster than the actual time, and a control computer corrects this based on the signal from the Mainflingen time signal transmitter near Frankfurt. The brief stopping of the hour ring is imperceptible to the human eye but visible in time-lapse recordings.

Address

Alexanderplatz 1
10178 Berlin