30 St Mary Axe is a modern, sustainable building located in London's financial district. The building is also widely known as the the Gherkin building and previously called the Swiss Re Building. It was built in 2003 and opened in 2004. In 1992 the Baltic Exchange (a trading center) was bombed, leaving an area for new architecture. 30 St Mary Axe took over this absent spot. The building is located on St Mary Axe Street, giving its name. The building has become an icon for London, as it is unique and very modern.
The architects and engineer designed the building to consume half of the typical amount of energy that a similar building would use. Air spaces between each floor create 6 shafts for a natural ventilation system that insulates the office spaces between. For what seems to be a curved building, there is only one actual curved window at the very top of the building. The overall structure is very stiff and doesn't require a lot of reinforcement because of its triangle perimeter.