Sydney Opera House – (we have a large proportion of antipodeans in our office!) The design of Jorn Utzon’s ground-breaking, winning entry in a global design competition challenged the accepted construction methods of the time, combining a clever use of geometry, mathematics and textures to evolve the shell structures that form the sail shapes enclosing the internal spaces. The use of such innovative solutions in response to traditional theatre design and challenging site conditions delivered a form that results in a dominant presence from all aspects, with a silhouette that is undisputedly one of the most recognised in global architecture.