Completed in 1932 after nine years of construction, the steel arch bridge spans 503 meters over Sydney Harbour. The main span is the 4th longest arch in the world, just one meter shorter than the Bayonne Bridge in New York, NY. The bridge was designed by John Bradfield who took the design idea from New York's Hell Gate Bridge. The steel arch was Sydney's tallest structure from 1932 to 1967 and is still the World's tallest arch, towering 134 meters over the waterline. The clearance below from highest point of the deck to the waterline is 49 meters. The deck has eight road lanes of which two were tram tracks until 1958, two rail road tracks, a pedestrian lane on the eastern side and a bicycle lane on the western side. The steelwork of which 79% was imported from England, weighs about 39,000 tonnes and is held together with 6 million rivets. The pylons are 89 meters tall and made of concrete and granite. The pylons have no significant structural purpose, other than providing extra force to keep the arch's anchoring points stationary, and prevent the arch from collapsing. The approach ramps are modeled very basically, because I didn't have sufficient photos of them and the main span is already complex enough.