The world's oldest surviving clipper will be transferred to its new owners ahead of its final journey from Scotland to Australia.
The City of Adelaide, built in 1864 to take migrants from Europe to Australia, is being readied to voyage south for the first time in more than 125 years.
It has been kept on a slipway at the Scottish Maritime Museum in Irvine, North Ayrshire, since it was salvaged in 1992 after sinking in the Clyde the previous year.
The museum could not afford to refurbish the ship and had applied to demolish it in order to save some parts of the vessel.
The new owner, Clipper Ship City of Adelaide, launched a successful campaign to save and relocate the vessel, which will now become part of a new maritime heritage park in South Australia. The group beat a rival bid from campaigners in Sunderland, where the ship was built.
The clipper will be formally handed over at a ceremony at the museum's Linthouse building on Friday before beginning the first leg of its 13,670-mile (22,000km) journey.
It had been regarded as unrecoverable because of the silted river and protected wetland areas around its berth in Irvine, but engineers in Australia created a steel cradle to allow the ship to be rolled across a temporary bridge over the river surface and on to a low-draft barge.
The City of Adelaide is due to leave Irvine within days, depending on weather conditions.
The vessel will be taken by barge to Greenwich in southeast London, where it will be moored beside its sister ship, the Cutty Sark, before being lifted into the hold of a cargo ship to make the journey to Australia.
The craft, which in later years was used as a hospital ship, a training boat and a clubhouse, is expected to arrive in Adelaide early next year.
Clipper Ship City of Adelaide director Peter Christopher said: "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.
"This has been a team project from the start, and the level of commitment and passion has been quite extraordinary.
"We have had great support from the Australian and Scottish governments and local councils, but nearly a third of the money required to get her back has come from public donations and a similar amount from South Australian industry."
