Crowds gathered to catch a last glimpse of the City of Adelaide as she set off from Irvine harbour after having been loaded on a barge.
The ship is making one last trip to the place it is named after and to which she transported thousands of emigrants during 28 years of working life as a Victorian transport vessel. It is not due to arrive until next spring.
She has been waiting for days for the right weather to depart.
The ship, which is classed as a listed building, will be transported by container ship to Australia after a campaign raised millions of pounds to restore it.
It is hoped she will become a major maritime attraction.
The vessel was built in Sunderland in 1864 but has been in Scotland since the 1880s and around the Clyde since 1924, when she was converted into a training ship and renamed HMS Carrick.
In 1991, when it was then known as The Carrick, the ship sank at Princes Dock, Glasgow. It lay on the bottom of the river for a year before being raised and returned to Irvine.
David Mann, director of the Scottish Maritime Museum said: "It was fantastic but slightly sad to see the City Of Adelaide depart Irvine harbour in front of such a large crowd.
"It is great all the hard work by the directors and their contractors paid off."
The trip will be a long way from its sad sinking in Glasgow 22 years ago.
She sank a few times before that and, on one occasion, Evening Times photographer Martin Shields was on the spot to capture some dramatic shots of the historic vessel as the water poured in and firefighters scrambled to save valuable items.
Martin said: "I was out on a job in 1989 and we spotted all these fire engines and it was clear she was in bother.
"Back then there was less of a problem with health and safety and we were able to get on and take some photos below deck.
"She is a lovely ship. It's great to see her being preserved."