The vessel – which is the first cruise ship to undergo work at the site for more than 25 years – arrived on 28 October for a 14-day refurbishment, which included steel repairs, an overhaul of the shafts and propellers, and a new application of underwater paint.
The ship sailed out of the site on Saturday (12 November) ahead of a Northern Lights cruise which departed the city on Sunday (13 November).
Peter Deer, managing director of Fred Olsen Cruise Lines, said: "I would like to thank the people of Liverpool, Birkenhead and Cammell Laird for looking after our ship Borealis during her time in dry dock.