30 St. Mary Axe or “The Gherkin” is a tower in London’s financial district. Completed in 2004, this unique building is home to offices, shops, and restaurants. Its conical shape and argyle pattern make it instantly recognizable and it has appeared in films, tv shows, and video games.
It has received numerous awards including the Stirling Prize, which is given to the “most outstanding building built or designed in Britain over the preceding year.”
Its circular layout contains an asterisk-shaped floor plan. This is unusual because neither is as flexible as a square one.
The Gherkin has no interior columns. This feat is achieved by the use of an exoskeleton which redistributes the vertical loads.
At ground level, it has a compact circular footprint. It bulges outward from the ground to the 21st floor and tapers off after that. This allows for more interior space without crowding neighboring buildings.
As the sun passes overhead the argyle pattern created by triangular glass panels can seem to simmer. Two types of glass were used, gray-tinted and clear. The gray-tinted glass was selected to reduce solar gain.
The Gherkin is certainly interesting, but by no means is it London’s only unusual structure. And more are on the way. As of March, 2016, there were 436 towers in the works!