The Sydney Opera House is an amazing structure that serves as a landmark to the city and its architecture. The story of its design by Danish architect Jørn Utzon in 1957  and its storied construction are worthy of a Hollywood script, with equal parts intrigue, charismatic personalities and technical innovation that took 16 years to complete. But the precast components that create the iconic "sails" are what lands it on my personal "Seven Wonders" list.