The artwork is in place for 24 hours
Sydney Opera House has been transformed into a forest for 24 hours, as part of a festival of contemporary art.
The installation, one of the biggest art works Australia has ever witnessed, is by French artist Pierre Huyghe.
The concert hall's seats have been temporarily taken out and replaced with thousands of trees, shrubs and plants.
The BBC's Sydney correspondent Nick Bryant says the work is designed to explore the relationship between nature and culture.
A singer guides visitors through the artwork
"This really does have the wow factor - the cavernous space of the concert hall at the Opera House transformed into this magical rainforest," he said.
"It looks like a very big, and a very beautiful botanical garden."
The installation is part of Sydney's Biennale 2008.