This elegant solution simplified the roof’s construction and reduced waste, enabling the building of the vaulted roof to begin in 1963. But as the contractors worked on executing Utzon’s vision, the project was dogged by labour disputes, design changes and rising material costs, making its budget balloon and its potential completion date disappear into the distance. “By 1962, the cost had risen to A£12.5m, and now everybody admitted they were only guessing,” said Philpott. “The opening day was postponed and postponed again. It had been planned for Australia Day 1963, it was put off until early 1964, then until sometime in 1966, and now no one is bold enough even to predict the year the doors may eventually open.”

The project’s biggest government supporter, Premier Cahill, had taken ill just months after building work had started. On his deathbed in 1959, he had made his Minister for Public Works, Norman Ryan, promise not to let the Opera House fail. Ryan, when interviewed by the BBC’s Philpott in 1965, gamely made a spirited defence of the project, but by this time frustration with its mounting costs and endless delays was palpable. “I wasn’t sure whether to admit to working on it at the time,” admitted Zunz. “If you went into a taxi, you got an earful of all the money that was being wasted, and God knows what.”

Adding to this contentious atmosphere, a few months after Ryan’s BBC interview, Robert Askin, who had vocally opposed the project, was elected the New South Wales Premier. He appointed Davis Hughes as the new Minister for Public Works, who clashed repeatedly with Utzon. Hughes, determined to rein in spending, began to challenge the architect’s costs and schedules, demanding a full set of working drawings for the interiors – the next stage of the project. “The whole situation started going downhill,” said Zunz. “Utzon couldn’t, wouldn’t, anyway didn’t produce the documents his client desired.” In retaliation, Hughes refused the payments demanded by the construction team, which left Utzon unable to pay his staff. In 1966, the Danish architect resigned from the project and left Australia, never returning to see his Opera House completed. 

Utzon’s resignation led to a public outcry, with 1,000 people taking to Sydney’s streets on 3 March 1966 to demand that he be reinstated. Instead, Hughes appointed a new panel of Australian architects to complete the interior as well as the glass walls. But if Hughes thought this would reduce costs and speed up the project, he was very much mistaken.

Overcoming the odds

The new team scrapped most of Utzon’s plans for the interior and radically redesigned it. Utzon had envisioned a dual purpose for the main hall, as an opera venue and a concert hall, but this was now viewed as unworkable, leading to the already installed stage production machinery having to be demolished. The new design also meant that each of the hundreds of pieces of glass in the interior walls needed to be cut to a unique size and shape, which continued to pile on the costs. The Sydney Opera House’s spiralling bill was pushed even higher when a labour dispute by union workers, over the dismissal of a worker and demands for better wages, culminated in a sit-in strike at the site in 1972. 

But the following year, the monumental undertaking that was the construction of the Sydney Opera House was finally completed. Ten years late and 14 times over its initial budget, it came in at a cost of A$102m (£51m).

It was formally opened by Queen Elizabeth II on 20 October 1973. The monarch praised the stunning building that had “captured the imagination of the world” while also wryly mentioning that “I understand that its construction has not been totally without problems”. Utzon declined to attend its opening, writing to Premier Askin that he couldn’t “see anything positive” in the interior work done by the Australian architects and it would not be possible for him “to avoid making very negative statements”. 

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The Danish architect did end up making peace and reengaging with the Sydney Opera House project in 1999, agreeing to work on the A$66m (£33m) renovation of its interior. In September 2004, the Reception Hall was renamed the Utzon Room in his honour after being redesigned by him.

In the years since its completion, acclaim for Sydney Opera House’s visionary architecture has only grown. Its distinctive sculptural form has made it one of the most immediately recognisable buildings in the world. More than 10.9m people visit it annually, and it has come to epitomise the Australian national identity, its soaring roof a celebration of creativity, culture and ambition in the face of seemingly insurmountable odds.

As a venue, it has played host to everyone from Bob Dylan, Ella Fitzgerald and Sammy Davis Jnr to The Cure, Björk and Massive Attack. In 1980, Arnold Schwarzenegger won his final body-building title there, and 10 years later anti-apartheid leader Nelson Mandela made one of his first major speeches from its steps following his release from prison. In 2004, Cathy Freeman, the first Aboriginal athlete to win an individual Olympic gold medal, opened the Olympic torch relay from outside the building. Its eye-catching roof is illuminated every year as part of Vivid Sydney, the city’s festival of light, music and ideas, and in 2017, stories of Indigenous Australia told in vibrant animations were projected onto it.

In 2007, the building that had been brought about by a combination of art, engineering and sheer bloody-minded perseverance was formally recognised as a World Heritage Site by Unesco. On recommending its inclusion, the International Council on Monuments and Sites declared: “The Sydney Opera House stands by itself as one of the indisputable masterpieces of human creativity, not only in the 20th Century but in the history of humankind.”

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