The final full day on the Celebrity Constellation cruise offered a menu of attractions that pretty much overwhelmed even the most ambitious of shore-going travelers.

Start with Naples itself. One day cannot adequately convey the history and energy and madness of the First World city that most closely resembles a Third World city.

But then you might want to take a trip out of town. One option? The memorable ruins of Pompeii, destroyed by the eruption of Vesuvius 20 centuries ago, but leaving behind a ghostly tableau of how Romans lived and played in the First Century AD.

Another option? A boat over to the island of Capri, known for a blue grotto, upscale tourism and the former home of the brutal Roman emperor Tiberius.

How about a bus trip to Sorrento, where ceramics of the sort many travelers adore are made by the truck load every day.

Or a boat ride down the Amalfi Coast, or a gastronomic tour of Napoli?

We went with Topic 1: A bus tour of the busiest, nuttiest, loudest big city in the civilized world. Hey, at least the garbage was being picked up this week. Or most of it, anyway.

I had been in Naples once before … well, once before on one trip to Italy — three individual soccer games in Naples during the Italia 1990 World Cup. The third of the three was Argentina’s buzz-kill shoot-out victory over hosts Italy, the game that made me miss my train and led to another adventure to be recalled some other time.

On each of the three occasions I saw a game in Naples, the drill was “get to the stadium, see game, file stories, get back to the train station heading for Rome.”

This was the light of day, and Naples was doing its thing without any interference from the World Cup.

I didn’t really see the city, back then, and its aggressive, horn-honking, chaotic majesty that makes it one of the world’s great slow-motion train wrecks.

We took one of those double-decker buses, which seem too cliche-touristy but really offers the only way to get any kind of sense of a city in a few hours.

We were off early, to the National Archeology Museum, most famous for taking the best of everything from the Pompeii ruins.

Some great stuff in there, especially mosaics, but the Pompeii artifacts exhibition would not be open till 2 p.m. For no good reason we could ascertain beyond them wanting to charge admission twice.

Also, the sprawling building looks just this side of ramshackle, ready to join Pompeii in ruins, except these would be self-inflicted.

We got our fill of marble statuary, as well as a stop at the “secret” exhibit of Roman erotic art, a room which women were not allowed to enter until the 20th century, lest their delicate sensibilities be so rudely attacked.

Then it was back to the streets, and the tiny cars and sputtering scooters and lumbering buses were the noisy backdrop to our climb to the top of the city, which is built into several hills.

An interesting and amusing sidelight of this was the commentary available, via ear buds, where the female narrator embraced blunt acceptance of Naples’s problems, of which there are many. And came up with sentences like, “While it may look ramshackle and a bit dreary, Neapolitans never give up and it is their indomitable spirit that makes them find a way to carry on.”

No bus tour on the planet is so painfully candid. Maybe to short-circuit the listener from coming to his own conclusions.

We asked a young woman, who worked for the bus company, about getting off at stop 10 and walking to the boat, rather than stop 11, which was closer to the boat.

She essentially said it was too dangerous to exit at stop 10 and she would be happier if we waited till stop 11. Naples being one of the most dangerous cities in the world, we often were told.

So, down to the port where the boat was waiting, and in the meantime we were all but kidnapped by a restaurant tout, who handed us over to a waiter with a wise-guy patter in pretty good English, and we had a very fine buffala-mozzarella pizza and two glasses of beer for 16 euros. Which was a pretty good deal, especially when two free shots of limoncello were offered with pride by our waiter who, we noticed, managed to do his pizza-slinging job even while ogling every woman who came within 50 yards of him. Talk about a head on a swivel.

Then back to the ship where one of us was on the sun deck within a few minutes, as we waited the X number of hours required for our more-ambitious shipmates to return from their more-distant pursuits, “an easy bus ride” (hah) from smoggy, frantic, frenetic, madcap, alarming Naples.

I recommend it, but see it soon, before it collapses under its own reckless, riveting weight.