City of London tall office buildings including the 600-foot (183 m), 47-storey Natwest Tower, the first skyscraper in the UK. Office space development has intensified especially in the central, northern and eastern parts, with skyscrapers including 30 St. Mary Axe ("the Gherkin"'), Leadenhall Building ("the Cheesegrater"), 20 Fenchurch Street ("the Walkie-Talkie"), the Broadgate Tower and the Heron Tower, the tallest in the City. Another skyscraper, 22 Bishopsgate, is under construction. The main residential section of the City today is the Barbican Estate, constructed between 1965 and 1976. The Museum of London is based there, as are a number of other services provided by
St Mary Axe of the former buildings of the Baltic Exchange and the UK Chamber of Shipping (destroyed by an IRA bomb in 1992). The street originates as a turn off Houndsditch at its northern end, with traffic flowing one-way southbound, and it originates at its southern end as a turn off Leadenhall Street, with traffic flowing one-way northbound. Both one-way portions of St Mary Axe converge at Bevis Marks, where traffic is forced westward into Camomile Street. "Number 70 St Mary Axe" appears in several novels by the British author Tom Holt as the address of a firm of sorcerers headed by