Artist rendering of Marella Explorer 2

We're back onboard Marella Explorer, the latest -- and largest -- ship to join the Marella fleet. We first experienced the ship in May at its launch in Palma, which included a performance by popstar Craig David, but we were keen to get back onboard to discover the ship on an actual cruise. We're currently in Naples, en route to Livorno, as part of a weeklong Mediterranean itinerary.

Here's what stands out for us.

It's an Old Ship But Doesn't Feel Like It

Marella Explorer is not a new ship; it was previously called Mein Schiff 1 and sailed for nine years for Tui Cruises (before that the ship sailed as Celebrity Galaxy and was the ship on which Jane McDonald first became famous on the show The Cruise). However, you'd be hard-pressed to tell it sailed as a German ship. The amount of time, effort and thought that has gone into transforming it from a ship aimed squarely at the German market to one aimed squarely at the British market is astonishing. It's almost impossible to tell, in fact. There are just a few tiny things: the gym equipment welcomes you in German, and the Wi-Fi log in spells cabins "kabines". Everything else -- the restaurants, bars, public spaces and cabins -- has been completely transformed and looks and smells brand new.

The only aspect that can't be changed, of course, is the structure of the ship, but this plays to Marella's advantage. Corridors are wide (at least double the width of modern ships); there is acres of top deck space, which is usually cordoned off or at a premium on modern ships; the Promenade on Deck 6 is very wide; and balconies, certainly in the premium cabins, are vast -- big enough for a table and two chairs, two loungers and a hammock. Another thing that has really struck us is the amount of space in bars and lounges. The Squid and Anchor, the Lounge and Indigo are all huge spaces with lots of seating and exceptionally large bars, thus avoiding the two-, three- and four-deep queues that you will find on many other ships.

It's Cheap as Ships

We've often wondered why, when ships are duty free paradises, drinks -- cocktails, in particular -- are so expensive. Not so on Marella Explorer, where the drinks either cost just a small supplement or are free. (Non-premium beers, wines and selected cocktails are included in your fare, and there are even dispensers in the main buffet.) For example, you can pick up a specialty cocktail for £2.50 -- £2.50!; bottles of wine start at £16, and a large glass is £3.50. Beers are around the same price as glass of wine. Similarly, the speciality coffees are just £1.35 for a regular latte or £1.55 for a large. That's at least a pound cheaper than on the High Street. And here's a novel idea: instead of charging for water and wasting plastic bottles, the line has installed water fountains on each floor and encourages people to reuse their plastic water bottles or bring their own. And finally, all tips are included, so there are no nasty shocks at the end of your cruise (or queuing at Reception to get them removed from your bill).

It's Full of Little Touches

Like the aforementioned water fountains, there are so many little touches that we've noticed -- thoughtful ones, that make you feel at home, like kettles in cabins (and coffee machines in Junior Suites). And stylish ones that make you think "that's pretty cool" -- like taps that glow blue or red when you run them. The design of a Junior Suite means the bed faces the window, rather than being placed perpendicular to it. Instead of nasty plastic containers with generic body wash/shampoo, there are pretty ceramic ones secured to the shower walls and next to the basins. Hammocks on balconies! (We wrote about this in May, but we still can't get over it.) There's also a gin and whisky tasting bar to the side of the main bar, and if you have the Premium Package, a 45-minute tasting is included. One of the shops in the shopping arcade was closed for lunch, but an assistant in a nearby store opened it up for us. The latter is just one example of consistently good service.

It Feels High End

Tui and, by extension, Marella have no pretensions to be a luxury brand. This ship is aimed squarely at mid-market cruisers. However (and this is a good thing), we've noticed touches that take this ship into a 4- or even 4.5-star category. The Champneys Spa is probably the main aspect that does this, and we raved about that in May. As well as being vast, it oozes luxury in terms of its decor, the staff uniforms and the products on sale.

The main Reception onboard -- though lacking the "wow" factor found on many ships in terms of a huge atrium -- is understated luxury. With white marble flooring (speckled with black inlay), glass partitions, white walls and a sweeping staircase, it looks and feels just like a luxury hotel. It's the same with the Broad Street Shopping Arcade, which has the feel of an upmarket department store. Carpets and decor in corridors and public spaces add to the feel, and The Coffee Port has a display of the most exquisite hand-crafted chocolates, which you'd usually find at a bespoke chocolatier.

Champneys Spa Is Superb

We raved about the spa when we first got onboard -- the sheer scale of it on a ship this size is extraordinary -- but we've been spending a lot of time in there on this cruise and have discovered more aspects we love. One is this Persian garden, an open-to-the-elements space, complete with swinging chairs. Also of note is a relaxation room with piped music, loungers and calming blue light. But what really stands out is a vast couples' treatment room, complete with bath, huge oval lounger, private sauna (!) and an outside space directly overlooking the bridge. It's £389 per day, which includes four treatments (two each, which would set you back around £320 on their own). We also must tip our hat to the fact the thermal suite costs just £15 for the day, which is a steal.

It's hard to find fault at any level, but there are a few misses. If we're being picky, we'd question why no one in the main dining room knows anything about wine. (But maybe there's no need?) Food in the main dining room is a bit hit-or-miss, and portions could be a lot bigger. The kids club, though bright, airy and staffed with some of the friendliest crew we've ever met, is tiny; we query how it will cope, as it holds 32 kids and the ship in high season can carry more than 200. Further, the two main pools, though large and deep, are salt water, probably due to the ship's age.

Marella inspires loyalty with its long-serving staff and repeat passengers, both carried over from the line's days as Thomson; being onboard Marella Explorer, we can certainly see why. The line knows its clientele thoroughly, inside and out -- exactly what they need and want. And, in the case of this ship, Marella has even anticipated what passengers might not yet know they need or want with first-time additions like a silent disco, high-end spa and gin tasting bar. This ship is an outstanding addition to the Marella fleet.

--By Adam Coulter, Managing Editor, UK