30 St Mary Axe (previously known as the Swiss Re Building and informally known as the Gherkin) is a commercial skyscraper in London's primary financial district, the City of London. It was completed in December 2003 and opened in April 2004. With 41 floors, it is 180 metres (591 ft) tall and stands on the sites of the former Baltic Exchange and Chamber of Shipping, which were extensively damaged in 1992 in the Baltic Exchange bombing by a device placed by the Provisional IRA in St Mary Axe, a narrow street leading north from Leadenhall Street.