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SYDNEY - She's among the most famous Australians of all time, featured in countless movies, photographed by thousands daily, festooned with diamonds and sparklers, the No 1 guest on any serious party A-list.
Not bad for a squat, steely, grey, old dame of 75 who is very high maintenance to boot.
If Gallipoli was the first event to put a young Australian nation on the world map, in 1915, then Sydney's Harbour Bridge was the first structure to do so, in 1932.
She has defined Australia to the world for twice as long as her immeasurably more beautiful little sister, the Opera House, across the water on Bennelong Point.
And now that she turns 75 on March 19, Sydneysiders are inclined to throw a party for her, rather than get her to do all the entertaining, as she has during the bicentenary, the millennium, the Olympics and every New Year's Eve since 1998.
It's time to celebrate what makes her so great, even if it is no longer Australia's biggest bridge or, in the eyes of many a beholder, the loveliest.
Some hold the near-heretical view that there are even lovelier bridges in the same city, pointing, for example, to the graceful Anzac Bridge, a couple of kilometres upriver.
This could make her the Ringo Starr of Australian bridges - as John Lennon once remarked when asked if Ringo was the best drummer in the world: "He isn't even the best drummer in the Beatles."
American writer James Michener felt that way half a century ago when he observed: "To get on in Australia, you must make two observations. Say 'You have the most beautiful bridge in the world' and 'They tell me you trounced England again in the cricket'. The first statement will be a lie. Sydney Bridge is big, utilitarian and the symbol of Australia, like the Statue of Liberty or the Eiffel Tower. But it is very ugly. No Australian will admit this."
Visitors these days, by contrast, literally clamber over each other to rub shoulders with the mighty steel arch on a money-spinning tourist attraction called BridgeClimb. Almost 2 million climbers, royalty and commoners alike, have helped turn it into a A$10 million-a-year ($11.4 million) profit-maker in under a decade.
The bridge was not, however, an instant hit with everyone.
It arose during a bleak depression, and though it provided employment for many, it demanded the demolition of 800 homes, without a penny of compensation for their occupants.
It cost lives, too - 16 of the 1400 workforce died during construction, mostly by falling off.
And it prickled jealousies harboured by have-not provincials towards their richer city cousins.
"Rural taxpayers saw the vampire city, of which the bridge is so complete a symbol, sucking the life blood of the suffering country," wrote a disaffected bush dweller of the time.
The bridge cannot boast of pure, national achievement, either, for though it appeared three decades after federation it was still the product of colonialist thinking. It was built by the English firm Dorman Long, 80 per cent of its 39,000 tonnes of steel came from Middlesbrough and the 6 million rivets holding it together were made in Lancashire.
The British flag was flown alongside those of NSW and Australia on opening day in 1932, "partly to acknowledge the key role of the English company and partly, I suppose, because most Australians still regarded themselves as British", said Caroline Mackaness, bridge exhibition curator at the Museum of Sydney.
But the fact that Australian brawn could make it a reality amid the toughest of economic times must have been a tremendous source of pride in a young nation still smarting from its losses in the Great War.
"It was - and still is - considered a feat of world-class engineering that signified Australia's capacity and maturity as a nation," said Mackaness.
It cost a pretty penny - £10,057,170 7s 9d to be exact.
For a structure which cost twice the original estimate, it seems fitting that it was completed twice and declared open twice.
The two halves, held up by support cables which were slowly released, first clunked together on the afternoon of August 19, 1930, only to part that evening due to contracting metal. They were rejoined at 10pm, for good.
Two years later, just as NSW Premier Jack Lang was about to cut the ceremonial ribbon on opening day, Francis de Groot, a member of a right-wing paramilitary group called the New Guard, rode up on horseback.
He slashed the ribbon with his sword to make the point that King George V or his royal representative, the Governor-General, should have been doing the honours. Lang had to get out his scissors a second time.
De Groot was fined £5.
Maintaining the bridge has proved a never-ending task for teams of painters who once counted among their ranks Paul Hogan before he went on to Crocodile Dundee fame.
The first coat of its less than dazzling grey weather-proof paint - all 270,000 litres of it - took 14 years to apply. Spray guns are used now, but the task of stripping away old coats of toxic lead-based paint could, according to tour guides, take 5 years and $200 million.
Tolls have long since covered the cost of building the bridge - that happened in the 1980s.
But not only were the tolls retained, they were increased to help pay for Sydney's harbour tunnel.
From 20c in early decimal days to $3 now (southbound only), it is a far cry from 1932, when it cost a mere sixpence each way (half price for riders and horses).
You won't see many horses these days, as car traffic has increased from 11,000 a day to 160,000. But the Bradfield Highway, the road that crosses it, is still designated as a travelling stock route, meaning you can herd livestock across it, provided you give plenty of notice and do so between midnight and dawn.
Half a million people crossed the bridge on foot on its 50th birthday in 1982. A crowd of 250,000 took part in the reconciliation march in 2000, reaching across a symbolic divide to the "stolen generations" of Aborigines.
All records are likely to be broken on March 18 when the bridge gets its longest-ever rest from traffic - from 4.30am to 11pm - so the public can, in the words of event director Rachel Hurford, "recreate the overwhelming sense of celebration and joy" experienced on opening day in 1932.
Most - but not all - traffic passing underneath the bridge has been waterborne. Warplanes occasionally negotiated the 49m clearance during World War II, including on one memorable occasion a Lancaster bomber flown by Flight Lieutenant Peter Isaacson on a fund-raising stunt.
The bridge's nickname is supposed to be the "coathanger", because it loosely resembles one, though hardly anyone calls it that these days. It is simply The Bridge - no qualification necessary.
Chief engineer John Bradfield called it "a triumphant arch of steel humanising our landscape" and a "thing of beauty".
You can agree or disagree about that, but it's hard to dispute his contention that "it will assert itself long after we are gone".
It may be dwarfed physically now by the city it once overlooked, but it somehow remains the dominant force in Sydney's skyscape.
SPANNING TIME
Opened: March 19, 1932.
Cost: £10,057,170 7s 9d (paid off in 1988)
Length: 1149m.
Width: 49m (carrying eight lanes for cars, two rail tracks, pedestrian and bicycle paths).
Height: 134m (plus up to 180mm on hot days as steel expands).
Clearance between water and bridge: 49m.
Weight: 52,000 tonnes (including 39,000 tonnes for the steel arch alone).
Amount of concrete: 95,000 cu m.
Amount of granite: 17,000 cu m.
Amount of paint for one coat: 270,000 litres.
Most famous painter: Paul Hogan.
Number of rivets: 6 million.
Builder: Dorman and Long, of Middlesbrough, England.
Construction time: Eight years.
Number of workers: 1400.
Deaths: 16.
Tolls: Originally sixpence each way, now A$3 southbound only.
Cars per day: 11,000 in 1932, now 160,000.
Film and TV credits: Mad Max, Independence Day, Mission Impossible 2, Finding Nemo, Inspector Morse, JAG, McCloud.
Cost to climb: From A$100 per child and A$169 an adult.
- AAP