30 St Mary Axe ( known previously as the Swiss Re Building ) , 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 tall and stands on the former sites of the 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
Baltic Exchange bombing
Baltic Exchange bombing
30 St Mary Axe