Bolte Bridge Melbourne

The Bolte Bridge is a large twin Cantilever bridge in Melbourne, Victoria, Australia. It spans the Yarra River and Victoria Harbour in theDocklands precinct to the west of the Melbourne CBD. It forms part of the CityLink system of toll roads that connects the Tullamarine Freeway from the northern suburbs with the West Gate Freeway and the Domain and Burnley tunnels to the Monash Freeway and the south eastern suburbs.
The bridge was designed by architects Denton Corker Marshall and was built for head contractor Transurban by Baulderstone Hornibrook, construction taking three years from 1996 to 1999 and costing $75 million. It was named by Jeff Kennett, for former Premierof Victoria, Sir Henry Bolte because of its linking the West Gate, Monash and Tullamarine Freeways—projects commissioned or completed by the Bolte Government.
It is one of the largest balanced cantilever cast in situ box girder bridges in Australia. The superstructure is built as two independent bridges of variable depth, prestressed concrete box girders, separated by a 1.15 m clear gap between the structures.
The bridge features two 90 metre (295.2 ft high silver towers, situated on either side of the roadway at the midpoint of the bridge's span. These two towers are an aesthetic addition by the architects, and are not joined to the main body of the bridge.[1] These towers are hollow, and feature access ladders to a small roof top hatch. Until locked and surrounded by water, these towers were a popular target for urban explorers. It has four spans with two main spans of 173 metres (567.6 ft) and side spans of 72 metres (236.2 ft), giving an overall bridge length of 490 metres (1,607.6 ft). The bridge supports six lanes of automobile traffic. Access is prohibited to cyclists and pedestrians.
Other bridges in Australia of similar construction are the Gateway Bridge, Brisbane and Mooney Mooney Bridge near Gosford, north of Sydney.