The ship, Saga’s second new-build, joins Spirit of Adventure in Tilbury.
There, Adventure will lay up for the winter ahead of its inaugural cruise departing 5 February 2021 sailing to the Canary Islands.
Saga took delivery of Spirit of Adventure from shipbuilder Meyer Werft on 29 September.
The ship has 554 all-balcony cabins, and has a total capacity of 999 passengers.
Nigel Blanks, managing director of Saga Cruises, said Discovery and now Adventure had allowed the line to create a "boutique cruising experience".
"With Spirit of Adventure joining our fleet, we now have more choice for our guests with two unique ships," said Blanks.
