The Tasman Bridge in Tasmania, Australia, is struck by the bulk ore carrier Lake Illawarra, killing twelve people.

The Tasman Bridge is a prestressed concrete girder bridge connecting the Tasman Highway over the River Derwent in Hobart, Tasmania, Australia. When it opened on 29 March 1965, the Tasman was the longest prestressed concrete bridge in Australia, with a total length measuring 1,396 metres (4,580 ft), including approaches. The bridge provides a vital link between Hobart's city centre on the western shore and the City of Clarence on the eastern shore. Averaging 73,029 vehicle crossings per day, the bridge is the highest volume road section in Tasmania. It features five lanes of traffic including a central lane equipped for tidal flow operations and separated shared-use walkways on both sides, with ramp upgrades for improved access and cyclists completed in 2010.

Tasmania is an island state of Australia. It is located 240 kilometres to the south of the Australian mainland, and is separated from it by the Bass Strait. The state encompasses the main island of Tasmania, the 26th-largest island in the world, and the surrounding 1000 islands. It is Australia's smallest and least populous state, with 573,479 residents as of June 2023. The state capital and largest city is Hobart, with around 40% of the population living in the Greater Hobart area. Tasmania is the most decentralised state in Australia, with the lowest proportion of its residents living within its capital city.

The Tasman Bridge disaster occurred on the evening of 5 January 1975, in Hobart, the capital city of Australia's island state of Tasmania, when the bulk carrier Lake Illawarra, travelling up the River Derwent, collided with several pylons of the Tasman Bridge and caused a large section of the bridge deck to collapse onto the ship and into the river below. Twelve people were killed, including seven crew on board Lake Illawarra, and the five occupants of four cars which fell 45 metres (150 ft) after driving off the bridge. Hobart was cut off from its eastern suburbs, and the loss of the road connection had a major social impact. The ship's master was officially penalised for inattention and failure to handle his vessel in a seamanlike manner.