The City of Adelaide was built in 1864 to take migrants from Europe to Australia and was later a hospital ship, a training ship, and finally a clubhouse moored in the River Clyde in Glasgow.
When in Scotland it was flooded and has been stored on a slipway in Irvine, North Ayrshire, since 1992 where it was preserved by the Scottish Maritime Museum.
Management at the museum could not afford to refurbish the vessel and had applied to demolish it to save some of the parts of the ship, but the group Clipper Ship City of Adelaide applied to relocate it and the clipper is to be part of a South Australian maritime heritage park.
The ship was regarded as unrecoverable due to the silted river and protected wetland areas around it, but engineers in Australia created a steel cradle to allow the ship to be rolled across a temporary bridge over the river onto a low-draft barge. It will sail to London in September.
It will be moored beside its sister ship the Cutty Sark before being lifted on to a huge cargo ship to travel to Australia, where it is due to arrive by April next year.
Clipper Ship City of Adelaide director Peter Christopher said: "Recognising the opportunity of saving the world-heritage ship, Scottish Culture Minster Fiona Hyslop took the positive decision to call a study into any options for saving the ship. The Australian team's strategy stood out and offered the additional advantage of enhancing Scottish and Australian cultural ties in the process."
He added: "I can almost picture the spectacle as the clipper is transported up the River Thames to Greenwich, bringing together the two last original 19th century clipper ships."
The cradle made to lift the ship out of its berth in Irvine cost about £700,000 to build, with around one-third coming from public donations in Australia.