30 St Mary Axe (widely known informally as The Gherkin and previously as the Swiss Re Building) is a commercial neo-futuristic skyscraper in London's primary financial district, the City of London. It was completed in December 2003 and opened in April 2004.[4] With 41 storeys, it is 180 metres (591 ft) tall[3] and stands on the former sites of the Baltic Exchange and Chamber of Shipping, which were extensively damaged in 1992 by the explosion of a bomb placed by the Provisional IRA in St Mary Axe, the street from which the tower takes its name.[4][9]