In the eyes of the 1 to 2 million people who visit it every year - locals, tourists, artists and architects - Barcelona's Sagrada Familia church is the greatest work of architectural genius of the modern era.
Workmen laid the foundations for Antoni Gaudí's extraordinary cathedral in 1882; when it is completed, somewhere around the middle of next century, it will be able to accommodate a congregation of 15,000.
La Sagrada Familia - or "Church of the Holy Family" - is a work in time, as well as in space. Over the 74 years since the great Catalonian architect's death, his dreaming spires have tantalised generations of architects and engineers who have sought to realise their enigmatic geometry in stone.
Nothing about Gaudí's cathedral is conventional, not even the means for its completion.
Half a world away from Barcelona, in the converted woolstores of Deakin University's School of Architecture and Building in Geelong, Professor Mark Burry is using modified aeronautical engineering software to translate the Sagrada's soaring curves into working designs for Barcelona's construction team, and engaging the minds of a new generation of young architects in the unique challenges posed by the world's most radical piece of architecture.
Professor Burry heads the research and development project for La Sagrada Familia Church, and is a key member of a team of five architects who have been using high-level computer-aided design applications during the past decade, to realise Gaudi's masterpiece in stone.
"Antoni Gaudí is one of the world's most revered figures," says Professor Burry. "La Sagrada Familia is an unusual project, because we are trying to build it to his original design, without compromise, from his original plaster of paris models.
"Translating its structure into working drawings makes the greatest possible demands on modern architectural software. Conventional software was developed to handle lines and simple curves and isn't up to the task, so I have adapted aeronautical software - Deakin University is the world's premier institution in this field."
Professor Burry's involvement in the project traces to the Masters thesis he wrote as a young architecture student at Cambridge University in the UK in 1979.
"In my thesis I asked two questions that hit the button," Professor Burry said. "What was the authority of the construction committee to finish the building the way Gaudí designed it, when the architect had died 53 years earlier, and how was his design being communicated to the people working on the building?
"The answer to the first question is scholarship. The answer to the second is via a precise description of the building."
"The building challenges the notion of the sole author. Teamwork is crucial - we have never experienced a single dispute on site. The division of labor has evolved in a way that means everyone has a clear understanding of what their job is, and there is an atmosphere of mutual respect.
"The leader of the construction team is a 74-year-old Jordi Bonet Armangol, who is the son of one of the last people to work with Gaudí, and a previous director himself."
Professor Burry sees an "absolute parallel" between the construction of La Sagrada Familia after Gaudí's death, and the construction of Sydney's famed Opera House after its Danish architect, Joern Utzon, severed his ties with project in the 1960s, in protest at the government-funded construction authority's attempts to save costs by modifying its "impossible" design.
"You don't slate somebody for designing the impossible. You use human ingenuity to achieve the possible," he said.
Despite La Sagrada Familia's radical appearance, Professor Burry says it is less eclectic than it appears to the eye. "What you see is a series of curved surfaces, produced by warping straight lines. The various components of the building can be described as curved templates joined by straight lines.
"There is a precise geometry beneath the surface. Gaudí put in place a system that describes the architecture very precisely.
"To some it might seem just a matter of scaling from his original models. But my task is to investigate his original models and interpret what he meant.
"His geometry makes that practical, but there's a political reason for building it exactly as he defined it - we cannot be accused at some time in the future of building a Gaudí pastiche."
Professor Burry makes several visits a year to Barcelona, but cannot be continuously on site to solve problems, so he uses E-mail to communicate. The 9-hour time difference between Geelong and Barcelona is convenient; the on-site architects can call him to discuss a problem during his working hours, and he can usually solve it while they sleeps, so the workers can proceed when they arrive on site the next morning.
Professor Burry says Gaudí knew how long his masterpiece would take to complete; in 1914, he gave up all other commissions, moved onto the site, and spent the last 12 years of his life working on it full time.
"All the books on Gaudí's life and works finish around 1914. My scholarship since 1979 has focused on describing what went on during those 12 years, and it has been my privilege to do so.
"I've been working on the project for the greater part of my professional life -20 years. At the beginning, I believed it had no obvious ending point because construction was proceeding so slowly - in took 23 years, between 1954 and 1977, just to complete the second transept, which Gaudí had begun before his death.
"But since 1989, when I became involved with computer-aided design, we've seen a tremendous acceleration. I can now actually envisage it being completed, perhaps before the middle of next century.
"Funding isn't so much of a problem now - enough money comes from the million or so people a year who pay to see it, but site constraints prevent us building it much faster. If they changed the building to accommodate a new construction paradigm, it would breach the spirit of Gaudí's concept.
"A 50-year horizon may seem conservative, but in my opinion, Catalans are a very conservative people, in the best sense of the word."
Some of the original sandstone structures built in Gaudí's day have already begun to decay, so maintenance and construction proceed in parallel. Given that the great cathedral will stand at least as long as the great Gothic cathedrals of Europe, it is now being constructed from a synthetic sandstone with the appearance and composition of the original.
Professor Burry says some people have questioned the function of the building - with the Catholic faith apparently in decline in modern Spain, there can be no guarantee half a century hence that it will fulfil the purpose for which it was conceived in 1882.
But he believes humans will never lose their sense of congregation - the cathedral will not want for users.
Construction reached a historic and symbolic phase last year when the two sides of the nave met, bridging the first segment of the roof.
"Everyone knows the Sagrada was designed by someone who died in 1926, but from that point upwards, the realisation of much of his design for the nave will be 100 per cent Deakin's University's work."
Locating such a historic project in Deakin's School of Architecture and Construction Management provides students with rich opportunities, says Professor Burry.
The rigor needed to translate Gaudí's models means students have an opportunity to study, at first hand, the mind of an architectural genius.
To do so, they must learn to use the world's most advanced architectural software - software that opens new design horizons inaccessible to past generations of architects.
Building La Sagrada Familia, says Professor Burry, is an exacting science - the university is a world leader in pre-cast concrete construction, and on-site fabrication techniques.
It also takes unique project-management skills to keep such an enormous project running efficiently, without compromising the safety of the million-odd visitors who swarm around the site each year.
Students also gain invaluable experience in communicating at a distance, a skill that must be mastered if the diverse skills of model-makers, architects and the artisans on site are to function as a seamless whole.
"We believe we're ahead of most architectural firms around the world in all these domains," Professor Burry said. "It's a heady mix of pure research into methodology, and applied research, putting the concepts into practice."