Lord Palumbo has given Mies van der Rohe's Mansion House Square archive—which includes models, photographs, and films—to the RIBA Collections. Considered one of the most important collections of architectural materials in the world, the donation to RIBA is an important step in preserving the design records and more broadly, for "documenting the stories behind architecture," says RIBA President, Ben Derbyshire. 

The seminal gift from the property developer and architecture connoisseur contains three large-scale models: one of the city of London; one of Mies van der Rohe's unrealized proposal for the Mansion House Square; and another of the building's underground shopping concourse. It also includes original feasibility drawings, bronze door handles and hinges, photomontages by architectural photographer John Donat and historical documents and objects related to the hotly-debated development.

Despite never being built, the German modernist's plans for Mansion House Square have been described by Richard Rogers as "the culmination of a master architect's life work." Contrastingly, it was described by Prince Charles at the time as "a giant glass stump"—a characterization that helped fuel popular outrage and vilification of the project. 

Commissioned by Lord Palumbo in the 60s, the plans ended up becoming the focus of one of the most famous post-War architecture planning controversies in the UK. It was eventually rejected in 1984, driving Lord Palumbo to then commission James Stirling's Number One Poultry, a pink post-modernist work—not without its own controversy—that was recently given Grade II listing. 

The unrealized design for Mansion House Square was revealed in detail for the first time last year as part of an exhibition at RIBA on the two disputed projects. The full collection, generously gifted by Lord Palumbo, will now become part of the Institute's Collections, joining over 4 million drawings, books, models and photographs.