The Batman Bridge near Sidmouth, Tasmania, is several kilometres downstream from Launceston and crosses the Tamar River. The reason for the bridge's peculiar looks is the geological conditions of the site where the bridge is situated. The western bank of the bridge has good rock structure (Jurassic dolerite) as foundation while the eastern bank has deep clay lying under the structure. It was therefore decided to build a cable stayed bridge with a leaning 97.6m "A" frame tower founded on the western bank to help support the four spans over poor foundation material.

The main span is supported by three sets of stays strung from the top of the tower at 48m centres. The tower, including the cross beam and cross bracing, is made of welded steel box sections. The roadway is supported by orthotropic steel decking with a two inch mastic asphalt surface above it. The decking is made of sections 10.4m wide and 3.4m long welded together to form a continuous length. The main reason for choosing the steel decking is to keep the overall weight down. Steel decking is decidedly lighter than concrete decking with an equivalent in strength. On a down side though, the steel decking required an unusually large amount of erection welding which is time consuming and expensive.
The superstructure consists of a steel truss which supports the steel deck at 9.1m centres and was assembled in 13.7m long segments prior to erection. All field connections for the trusses and other steel work were made by friction grip bolts. The bridge was constructed using an erection gantry which was situated on the previously erected bridge.
The tower consists of 40 sections each 4.6m high except for the top section which is 7m high. The pieces were assembled by a 32t derrick crane which was mounted on a specially designed climbing platform which ran on rails up the tower as construction progressed. Thirty-two permanent back stay cables were connected to the western abutment to balance out the weight of the main span. The eastern portion of the bridge is supported by four piers two of which are founded on 18.3m long steel piles driven into the clay.
The steel used for the Batman Bridge is of two types, mild steel for smaller members and notch-ductile steel for the larger members. All steel work was completely painted before leaving the suppliers in Melbourne and only required a small touch up on site. It had been given a complete treatment of Dimetcote with vinyl finishing coat.

Constructed by: Maunsell & Partners, Lewis Construction Co. Pty. Ltd.; Johns & Waygood Ltd.
Construction period: July 1964 to May 1968.
Materials: Steel
Dimensions:
• Span lengths: Main span of 205.9m,
• 1side span of 54.9m,
• 1 span of 47.9m and 3 spans of 41.1m
• Total length: 427m
• Deck width: 10.3m
• Deck Depth: 4.5m

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