The under-50s on our cruise were in the minority. Oriana appeals to a mature and almost exclusively British clientele, mainly couples, along with small groups of friends and middle-aged children travelling with one or both parents. A grumble among nimble footed single ladies was that there weren't enough spare men to dance with and no gentleman hosts.

Whilst some were on their first cruise, a lot of people were seafaring veterans, many loyal to the P&O brand and several recounting tales of feeling all at sea on the few occasions they'd defected to larger international vessels. Sociable and well-travelled, they were fun to talk to, and it was easy to see how friendships are often formed, demonstrated by several couples who originally met onboard and travel together each year.

They threw themselves wholeheartedly into the onboard activities and excursions, and each night when we headed to bed, we were outpaced by hardy octogenarians and nonagenarians burning the midnight oil.

Life onboard is relaxed and casual during the day, with many people happily wandering around in dressing gowns en route to the spa and pools. After 6 p.m., evenings are divided into black tie, smart and casual. Passengers can expect two formal nights on a seven-night cruise, four on 14-night itineraries and so on. There's a useful reminder and explanation of the daily dress code in the Horizon newsletter, and whilst the men donned tuxedos for the black-tie nights, women tended to go for posh frocks and cocktail dresses, rather than full-on ball gowns. (There also weren't the sequins and tiaras you get on some ships.) Smart turnout requires jackets for men, with dresses or separates for women, and just about anything goes on casual nights, including jeans. Whilst some casual evenings were further subdivided into '60s and '70s, it didn't make a huge amount of difference, and there's no obligation to break out the flares.

A £7 per person auto gratuity is added to your bill daily (for over 12s). Other tips are at your discretion.