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7 January 2015 Last updated at 17:04 GMT
The Hoegh Osaka car transporter was deliberately grounded on a sandbank to prevent it from completely overturning.
At high tide, when the sea level was at its highest, the ship began to float once again and move in the waves.
Authorities had been pumping water out of the vessel, which still contains 1,400 cars and construction equipment like diggers.
All crew were safely rescued off the ship on Saturday night.
It will now be towed to a safe place so officials can work out what should be done next.
A cargo ship carrying high-quality cars has "freed itself" from the sandbank where it has been stranded since Saturday.