As part of a new exhibition at the Royal Institute of British Architects, Mies’ 1969 design for a minimalist London tower has been realized in model form. Both the exhibition and the model have attracted a surprising amount of attention in the city. That’s because Mies’ tower—and the radically different building that was eventually constructed in its allotted space—were a battleground where London has debated a perennial question that all older cities must at times ask themselves. Is it ever possible to sensitively insert bold modern buildings into a historic neighborhood?

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That’s because the tower was due to be built at the heart of City of London, the British capital’s financial district and its longest-inhabited quarter. Indeed, the City only missed out on getting the Mies’ Tower now on display at RIBA thanks to a minor planning wrangle. A lean and elegant slab clad in brown glass, the design was warmly approved in 1969 (just after Mies’s death), but the corporation of London nonetheless felt it needed a plaza in front to complete it. The space chosen was then owned by many landlords in myriad small parcels, making acquisition extremely hard. This hugely complex process was only completed in the mid 1980s.

By then, Mies Tower was far out of fashion, while the florid Victorian building still occupying on the site was back in vogue. Major planning battles elsewhere in the city over the destruction of older buildings had made demolition newly contentious. Planners reconsidered rejected the tower design, opting instead for a plan from Britain’s leading post-modernist architect, James Stirling. The rejection, while not unpopular with the public, was thanks in no small part to that great scourge of modern architecture, Prince Charles. Having already dismissed London’s National Gallery extension as a “monstrous carbuncle” — and brought about its cancellation — Charles went on to criticize Mies’ design as a “giant glass stump.”

Stirling’s design, referred to in its built form as No.1, Poultry, could hardly have been more different. Broadly retaining the height and silhouette of the Victorian building it replaced, it was in just about every other way as mad as could be. 

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