Sea Princess (formerly Adonia) is a Sun-class cruise ship operated by the Princess Cruises line. She has three sister ships: Sun Princess and Dawn Princess in the Princess Cruises fleet and Oceana in the P&O Cruises fleet.

 The vessel was delivered to Princess Cruises from the shipbuilders of Fincantieri, Italy and began operation in 1998, under the name Sea Princess.Sea Princess was transferred to P&O Cruises in late 2002/early 2003. The vessel was renamed Adonia on 21 May 2003, at a launching ceremony with sister ship Oceana. The Princess Royal and her daughter Zara Phillips named the sister ships in the first double ship naming ceremony ever.

Adonia filled the gap left in the P&O Cruises fleet in the period between Arcadia leaving the fleet to become Ocean Village and the launch of the new Arcadia in 2005, when the vessel was transferred back to Princess Cruises taking her old name once more. The ship also received the"Movies Under The Stars" feature.

Whilst sailing as Adonia the vessel was dedicated as an adults only ship - which may have influenced the choice of name - Ad On ia - and for this period the children's playroom was refitted as a quiet lounge which featured massage chairs facing the panoramic windows. The children's play pool was converted into a Feng Shui relaxation area.


 From 11 September to 25 September 2009, the Sea Princess went into dry dock at BAE Systems, Pier 70 in San Francisco. The forward open deck area directly above the buffet restaurant became Princess’ “Oasis of Tranquility,” the Sanctuary, removing "splash pool". The propellers, rudders and thrusters were refurbished. The photo gallery area and Lotus Spa were remodelled and the passenger services desk re-floored.Film crews from the National Geographic channel were on hand to film the dry dock repairs. The ship's refurbishment was the subject of the 3 June 2010 episode of World's Toughest Fixes.

                                                                                 NOROVIRUS OUTBREAK
 At the end of May 2006, 250 people, including 18 crew, were affected by a norovirus. Evidence of a gastrointestinal virus had been found during the last two days of the previous cruise, but the company stated that it did not believe the two outbreaks to be linked. The passengers were notified of this occurrence by a letter found in their cabins after boarding. Although the ship's itinerary had been altered, and the vessel itself ordered to dock away from other vessels, no other countermeasures were effected. Sea Princess returned to port in Southampton a day early, and the vessel underwent a complete sanitisation and decontamination before resuming cruising. Passengers were offered a 30% refund and a £150 voucher for use on a later Princess cruise, some have demanded a full refund. Norovirus occurred again on the following cruise, although to a lesser extent, and visible precautions included waiter service at the buffets and the absence of salt and pepper shakers. This cruise was also affected by force 11-12 winds in the vicinity of Ushant, causing the first scheduled port to be missed, while the remaining itinerary remained unaltered. The ship was undamaged, the nearby Legend of the Seas suffered broken windows, and the Pride of Bilbao terminated its Spain-bound voyage in France due to storm damage. It is likely that the rough seas, caused increased use of the handrails, contributed to the difficulty of eradicating Legionella.