Since March this year, RIBA has been exploring Mies van der Rohe’s unrealised Mansion House Square project, alongside its built successor James Stirling Michael Wilford & Associates’ Number One Poultry.

Mies van der Rohe and James Stirling: Circling the Square exhibition has seen the projects presented together for the first time, offering a unique opportunity to trace the continuity in purpose and approach that unites two seemingly dissimilar architectural creations.

Commissioned by architectural patron and developer Lord Peter Palumbo, Mies van der Rohe designed his proposal for Mansion House Square at the very end of his career, between 1962 and his death in 1969. The classic Miesian glass tower of 19 storeys, accompanying public square and underground shopping centre would have been Mies’s first and only project in the UK. After a protracted planning process, the scheme was finally rejected in 1985.

Lord Palumbo then approached James Stirling, to conceive an alternative vision for the site. James Stirling, Michael Wilford & Associates’ Number One Poultry was completed in 1997, five years after Stirling’s untimely death. It is often cited as a masterpiece of the post-international style and has recently been awarded Grade II* listed status; while it still divides opinion, the building was designed with an acute understanding of both its historic surroundings and Mies’s earlier design.

The exhibition features newly restored models and materials about the Mies’ scheme on loan to the RIBA by Lord Palumbo, along with significant items from the Number One Poultry archive that provide an intimate insight into the workings of the Stirling office, from initial sketch ideas to Stirling’s famous ‘worm-eye’ axonometric views.

See what the press has been enthusing about – don’t miss this exhibition which closes on Sunday 20 August 2017.

A photomontage of the proposed tower block for the Mansion House Square scheme, 1 Poultry, City of London from 1983. © John Donat / RIBA Collections