As I floated through the open hatchway into the engine room, it was almost as if the scene had been frozen in time. The ship's charts were still in the rack and the phone was on the hook, but seaweed waved gracefully around the wreck, now home to octopus and fireworms.
On the seabed lay some Royal Navy china, smashed into pieces when the Lady Davinia, formerly HMS Greetham, was sunk. As I picked up one piece for a closer look, I was amused to discover it had been made in the Wedgwood factory just 15 minutes from where I grew up. Now 64 years later, it was half-buried in the sand, waiting to be rediscovered.
Just 15 metres above me, the busy cafés of Sliema, on Malta's east coast near the capital Valletta, were full of tourists relaxing in the sunshine.
The Mediterranean island, along with neighbouring Gozo, was last year voted the best diving destination in Europe by readers of Diver magazine in America, thanks to its clear, warm waters, and more than 30 underwater sites, with reefs, fish, caves and lagoons as well as the numerous wrecks. There's also a long diving season (from Easter through to November), and plenty of English-speaking instructors, so it's ideal for beginners from the UK.
It was all a long way from the swimming pool in Waterloo, London, where I'd started my dive training with the London Hellfins Scuba Diving Club. Although you can do the complete course in Malta, I wanted to get the theory lessons and pool training needed for the British Sub Aqua Club (BSAC) qualification done in the rainy UK, rather than being cooped up in a classroom while the sun shone outside.
The chlorine-scented pool that I'd practised in seemed a world away as I headed to my hotel, the Maritim Antonine Hotel & Spa in Mellieha, in the north of Malta.
While the UK froze, the sun was shining on the small hillside town, dominated by its huge baroque church, which is still the focal point of life on the island – although, for younger Maltese, it often seems to be a meeting point to start a night out.
Mellieha is also home to one of the island's best restaurants: Giuseppi's Wine Bar. Despite the uninspiring name – and its less-than-obvious entrance on St Helen Street – the seafood and local fish on the menu are spectacular, thanks to local chef Michael Diacono.
Over some Maltese wine, it was time for a quick introduction to the island by dive instructor Dave, who moved here three years ago from Lowestoft, enticed by the laid-back way of life, the year-round sunshine, and the fantastic choice of dive sites. He revealed it's the wrecks that make Maltese diving so special. And according to Dave, even on the rare occasions when there's bad weather, or when the wind makes the sea too rough for diving in one place, there is always a more sheltered option to try less than an hour's drive away.
The next morning, I shoehorned myself into a short pink wetsuit and some fetching black Neoprene boots as Dave led me into the calm waters of Qawra Bay, just along the coast from Mellieha, for my first ocean dive.
Things got off to a slow start when it turned out I was too light to sink, but, after a brief pause to fill my pockets with lead, I headed slowly down past shelves of seagrass towards the reef – while trying to keep an eye on my oxygen and my dive buddy, look out for landmarks to guide myself, stay balanced without shooting down to the seabed or up to the surface too fast, and still find the time to enjoy the scenery.
Once I'd worked out how to balance these various factors, I relaxed. After spotting a flying gurnard with its stunning iridescent blue markings hidden in the sand, I started to forget the strangeness of being completely surrounded by water.
The sea around Malta is home to grouper, rainbow wrasse and parrot fish, not to mention eels and more elusive barracudas and seahorses. Whether I dived one of the many wrecks or among the rock reefs and soft corals, there was plenty of underwater company, with shoals of brightly coloured fish darting over to investigate this curious bubble-blowing intruder.
With each dive I had more tests to pass, but also more exciting sites to explore. On Manoel Island, a spit of land opposite the capital Valletta, we strode off the sea wall to investigate a bombed barge, the Water Lighter X127.
Also known as the Carolita, she was sunk during the Second World War (probably after being mistaken for a submarine), and I could still make out the gaping hole left by the bomb that had finished her off.
The next day we explored the Lady Davinia. I got kitted up on the quayside, much to the amusement of a couple of local fishermen as I waddled to the shore weighed down with tank, lead and unwieldy flippers before vanishing under the waves. And when I emerged from the dive, my fifth, I was a certified Ocean Diver.
After swimming alongside them during the day, it felt almost rude to tuck into fish every evening. But specialities such as octopus carpaccio at harbourside restaurants around the island were too mouth-watering to miss.
Peppino's in St Julian's Bay, near Sliema, has tempted celebrities such as Brad Pitt, Madonna and Daniel Craig in the past, while they filmed in Malta (which has doubled as places such as Troy and Lebanon on film).
Meanwhile, in St Paul's Bay, a short drive from Mellieha, Tarragon Restaurant has already started winning local awards for its modern twist on Malta's classic favourites, such as black tiger prawns in champagne tempura.
For such a tiny island, there's plenty to see on dry land. And as I could only safely dive for a couple of hours every day, I did plenty of exploring – when I could drag myself away from the hotel's rooftop pool and the hot stone massages of its underground spa.
All roads lead to Valletta, around a half-hour drive from Mellieha. The fortified city, a grid of cobbled streets and steep steps, was built in the 16th century by the Knights of St John – otherwise known as the Knights Hospitaller.
Given the island as their base by a 16th-century king of Spain, and charged with protecting it against the Ottomans, they then built the new walled capital as a fortress to keep out the Turks.
The city is a Unesco World Heritage site, and walking through the streets takes you through centuries of history. Many of the façades of the auberges, the knights' grand former palaces, are unchanged, and you can visit the Grand Master's Palace, home to the Maltese government.
Most memorable for me, though, was the former capital of Mdina, the walled fortress in the centre of the island. Unlike Valletta's wide, planned streets, the twisting alleyways date from around the time of the Arab occupation of the island in the ninth century.
The city is closed to all but residents' cars. As I ambled to the bastion walls, past the Nunnery of St Benedict and the 700-year-old palazzos and casas of the Maltese nobility, nothing broke the quiet except the echoing clop of horse and carriage.
All too soon, though, it was time for my last dip: at Cirkewwa, in the island's far north. One of the best beginner sites, the water here is astonishingly clear, and, although I couldn't stray below 20 metres, the seabed at 36 metres looked temptingly close. One of the string of small underwater caves contained a statue of the Virgin Mary, and there was a natural stone arch in the rocks to swim through.
Above and below the waves, there are plenty of distractions in Malta.
* The writer flew as a guest of Air Malta (0845 070 1909; airmalta.com) which flies from Birmingham, Gatwick, Glasgow, Heathrow and Manchester.
* Maritim Antonine Hotel & Spa, Mellieha (00 356 2152 0923; maritim.com.mt), which this week has doubles from €100 with breakfast.
* The writer completed the BSAC Ocean Diver course at London's Hellfins Scuba Diving Club (hellfins.com; email@example.com) and at the Maltaqua dive school (00 356 2157 1873; maltaqua.com), where the complete course costs €360, or €220 if you have done the theory and training sessions with another school, club or instructor. For more details on courses, visit the British Sub-Aqua Club (bsac.com; 0151-350 6200)
* visitmalta.com; 00 356 2291 5000Reuse content