Editor's note: This ship is no longer sailing as part of the P&O fleet.
One of P&O Cruises' smallest and oldest ships, 1,880-passenger Oriana entered service in 1995, but a bow-to-stern facelift in 2011 and another makeover in 2016 have kept it feeling fresh. The very British ship is traditional in both design — with its defining Tiffany glass ceiling in the grand foyer and Art Deco accents throughout the ship — and values. (Picture formal nights, and assigned seating at dinner.)