The architectural icon that was never built
In 1921, a competition was held to design Berlin's first ever skyscraper.
The proposed tower was earmarked for a site on Friedrichstrasse, just north of the station, and would provide a striking new landmark to reflect the city's growing reputation as a modern, innovative metropolis.
The challenge attracted over 140 entries and did, indeed, provide ample evidence of the extraordinary talent of Germany's Weimar-era architects.
Karl Schneider. Image credit: karl-schneider-archiv.de
Hugo Häring. Image credit: fontecedro.it
Hans Poelzig. Image credit: wikiartis.com
And even though the development was ultimately shelved, several of the proposals have passed into history as modern classics - ideas only, but superb in conception.
None, however, proved more revolutionary than a design submitted by then little-known architect Mies van der Rohe, whose angular, glass-walled pinnacle was so ahead of its time that decades would pass before a similar building was actually constructed.
Mies van der Rohe Image: cloud-cuckoo.net
Mies van der Rohe Image: bdonline.co.uk
Mies' proposal to suspend sheets of glass from a supporting steel frame was unprecedented; a new aesthetic as well as a radical technological undertaking.
The design never progressed to the final stages of the competition, and it was only years later that his futuristic plans were hailed as an icon of modernity.
Yet in 1992, history had a chance to repeat itself when a similar competition was launched to create a building for exactly the same site.
Options included finally constructing Mies van der Rohe's translucent tower, but a design by Berliner Mark Braun was eventually chosen instead.
Plagued by controversy and subject to constant alteration, even the architect ultimately declared the result a 'disappointment'.
Friedrichstrasse finally had its high-rise tower - but nothing that could compare with the building that might have been.