It's 25 years since the City of London last got a new office tower, and it's never had one like the Swiss Re skyscraper - known as the Gherkin for its unique shape. Only now officially opened, it has already become visual shorthand for the capital.
By Megan Lane
BBC News Online Magazine
For three years London has watched the Swiss Re Tower gradually spiral out of the ashes of bombed Baltic Exchange site in the heart of the financial district.
In the initial stages of construction, its curved skeleton could only be glimpsed between the buildings crowding the City's tangled streets. But as it stretched skyward, it crested the packed skyline.
From this glazed tower, the capital spreads out beneath your feet. And just as those inside look out at London, London looks back.
For it can be seen from far and wide, its blue cigar-like shape providing a sharp contrast as it rises above box-like office blocks and familiar sights such as Tower Bridge, the London Eye and St Paul's Cathedral.
As an instant icon of 21st Century Britain, it has all but supplanted the Routemaster bus and Big Ben as shorthand for London on TV, in ads and on film. In Love Actually, it reared above Liam Neeson as his on-screen son told of a schoolyard crush during a stroll along the South Bank.
Even those who have worked long and hard on this newest addition to the skyline say it can still take them by surprise. For architect Norman Foster, whose firm Foster and Partners designed the building, this is one of its many charms.
"We did all the modelling, all the computer simulations to explore how it would look and how it would sit in the City. Yet I love that I still get unexpected views of it from all over London, and unexpected reflections of other buildings in its walls," Lord Foster told BBC News Online.
Those who work at 30 St Mary Axe every day - the employees of financial giant Swiss Re, and the construction team still hard at work fitting out the remaining floors - agree.
"The approach to the building is the best part of my day," says one.
The Gherkin dwarfs all around it
Another says that even though he has worked on the project for four years, he still delights in seeing it from vantage points around the capital.
Its innovative design, both in terms of its striking appearance and eco-friendly services - the design maximises daylight and natural ventilation so that it uses half the energy typically required by an office block - marks an evolution in architecture.
"It's part of a wider evolution toward more interesting forms of buildings around the world and here, wonderfully, in London," says Lord Foster.
Onward and upward
It is an evolution that is pushing ever upwards. A century ago, the capital's skyline was still dominated by St Paul's Cathedral. As late as the 1960s, building restrictions meant the chimney on Bankside Power Station - today Tate Modern - could not top St Paul's dome.
While 30 St Mary Axe is by no means London's tallest building - it's topped by the likes of the nearby Tower 42 (formerly the NatWest Tower) and Canary Wharf - it is the first of a cluster of planned skyscrapers.
The controversial "shard of glass"
The "shard of glass" - the 1,016ft London Bridge Tower - is set to be the tallest building in Europe. Last November the Deputy Prime Minister, John Prescott, gave the 66-storey project the go-ahead despite opposition from English Heritage (a body by no means opposed to height, as the Gherkin has its full support).
His decision is likely to encourage other developers to reach skywards. Work has started on a 47-storey glass tower in Manchester. And among the towers on the drawing board are projects in Brighton, and Aldgate and Bishopsgate in London.
But up is not the only way to create a distinctive building.
LONDON'S SKYSCRAPER SKYLINE
1. London Bridge Tower 303m - approved
2. Canary Wharf One Canada Square, 237m - completed 1991
3. Minerva Building St Botolph St, 216m or 247m with spire - approved
4. Leadenhall Building 215m or 234m with spire - proposed
5. Tower 42 183m - completed 1980
6. Heron Tower Bishopsgate, 183m or 222m with spire - approved
7. Swiss Re Tower 180m - completed 2004
The 40-storey Swiss Re tower is among 2004's most notable new buildings, but last year's landmarks were far more down to earth - quite literally.
The winner of the prestigious Stirling Prize for architecture was the low-slung Laban dance centre in east London, with the so-called "blinking eye" bridge which links Newcastle and Gateshead taking the 2002 award.
"Where going tall does make sense is in the inner city where buildings are densely-packed and there is little green space," says Lord Foster.