2018 is a milestone year for Australian architecture. It marks the centenary of architect Jørn Utzon’s birth, and 45 years since the opening of his most notable project, the Sydney Opera House. Parliament House in Canberra observes its 30th anniversary, and closer to home, the architecture program at the University of Sydney also celebrates a centenary.

The Sydney Architecture Festival began in 2007 on the forecourt of Customs House with the aim of lifting expectations in a growing city. This year, with the Sydney Opera House as a partner venue, its 12th annual edition will present a program that celebrates the big achievements in Australian architecture to date, and looks to them as a model for the future.

“What makes this festival different is the focus on our really iconic buildings and what they teach us about the conditions needed to make our cities and buildings really work,” says Tim Horton, NSW architects registrar and director of the Sydney Architecture Festival.

The theme “What makes a building truly great?” will underpin the program of talks, events and exhibitions spread across four days from Friday September 28 until Monday October 1.

For the first time, the Architecture Symposium will be held as part of the festival. Hosted at the Art Gallery of New South Wales, this full-day forum will unpack design projects by more than 20 of Australia’s best architects – many shown publicly for the first time.

“This is a ‘coming of age’ for Australian architects, and it will showcase the exceptional capacities of Australian architecture operating to deliver value in its economics, but more importantly, in the lasting public and social dividend architecture can bring to communities,” says Horton.

Another of Horton’s top picks is Beyond the Fence – Secrets of Australia’s Parliament House, which will see ABC’s Annabel Crabb interview Ric Thorp, one of the original architects of Parliament House, who rarely speaks in public about the topic.

“[It] will be a cracker. You’ll hear stories about designing the form of the building in a butter dish and getting stuck in an airlock with the Queen the day before the opening,” says Horton.

To close the festival, the fourth annual World Architecture Day Oration will be presented by New York-based writer, critic and judge Karen Stein. Stein has been a member of the prestigious Pritzker Prize jury for a decade, and is the first non-architect ever to present the oration. “I think she’ll start at the beginning – asking what architecture is really aiming to do, and what gives it meaning,” says Horton.

Sydney Architecture Festival runs from Friday September 28 until Monday October 1.