The Royal class is Princess Cruises' large-ship platform of the 2010s, built by Fincantieri at Monfalcone and delivered between 2012 and 2021. At 142,714 to 145,281 GT, the seven ships were the largest in the Princess fleet in their era, and the design is defined by the SeaWalk, a glass-bottomed walkway cantilevered beyond the ship's side high above the sea, balanced by an enlarged central Piazza as the social heart of the ship. Six ships — from Royal Princess to Discovery Princess — sail for Princess, while the same platform also produced Britannia as flagship for P&O Cruises, making this one of Fincantieri's most successful shared designs of the decade.
Member ships — 7 in Phase 1 of this directory
Sources: https://www.princess.com/en-au/news/backgrounders-and-fact-sheets/royal-princess-fun-facts