Ulysses, a 103-metre superyacht surprised Plymouth when it appeared on the Barbican on Monday 17 February.
The yacht moored up on the Barbican Landing Stage for a few days and has since moved to anchor in Plymouth Sound.
Plymouth Plus understands that the yacht came to the city to undergo vital maintenance work by Darthaven Services.
Engineers working for the company were spotted on the vessel over the past couple of days. The company has declined to comment.
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New Zealand's richest man and billionaire Graeme Hart owns the yacht which is one of the world's largest.
The yacht ranks in the top 5% by length and features a helipad, infinity pool, beach club, jacuzzi, cinema, gym, and a fleet of high-end boats and jet skis for exploring in style.
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@plymouthplus Billionaire's HUGE superyacht makes surprise visit to city #fyp #news #superyacht
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