HOVERING A FEW METRES BELOW THE SURFACE, I pinch my nose and equalise. The pressure in my ears released, I exhale, watching a trail of bubbles float languidly towards the surface. Daf Downes dived with Cydive Diving Centre, Paphos (00357 26934271 or visit www.cydive.com)
Above me, brilliant shafts of sunlight slash through the water. I empty what air remains in my BC and follow the dive boats anchor line downwards.
Ten metres down, we descend into a layer of much cooler water. I begin to envy the fact that Helen, my partner, has selected a thicker wetsuit for this, our deepest dive so far. But I remind myself that above the waves, the temperature is nudging the 30s.
Our small team regroups at our target depth of 18m. In our buddy pairs, we follow the slow fin-kicks of our dive leader down further. We level off at 30m, and at first all I see is a vast dark blur in the middle distance. It looms towards us, shrouded by fathoms of blue water.
Then, with each kick of my fins, the ships stern comes into focus. What I mistakenly took to be large rocks are the ships bulkhead doors. They are colossal. Here at last is the famous Zenobia.
Wide-eyed, we round the stern and see the full extent of the ship for the first time. Lying on its port side, the Zenobias midships plunge towards the seabed at more than 40m. The hull stretches far into the distance. I have never dived a wreck this size - its like coming face to face with some submerged monster.
I am reminded of the opening sequence of Titanic, where submersible cameras creep through underwater fog towards the ship. Like Titanic, the Zenobia met her end on her maiden voyage.
But thats where comparisons with the unsinkable Titanic end. Alan, our dive leader, had given us a brief history lesson as our boat chugged out of harbour.
Zenobia was one of the largest ro-ro ferries in the eastern Mediterranean, he had explained. She was a Swiss-registered vessel, more than 178m long, and weighed a mighty 10,000 tonnes - and thats before you add cargo.
The Zenobia had set off from Malmo in Sweden on her maiden voyage in June 1980, bound for Syria. But her captain noticed that she was steering oddly, and when she put into Larnaca Harbour in eastern Cyprus she was listing.
The Zenobias engineers discovered a serious malfunction with the computer system that was causing water to be pumped unstoppably into the ships ballast tanks, and the vessel had to be towed out of the harbour into deeper water, as the engineers struggled to remedy the defect.
But by the time the Zenobia was sloping to a 45 angle, the operational problems of carrying out a repair had become overwhelming.
Returning a ship of that size to the harbour would effectively cut Larnaca off to all other shipping, and the captains pleas to tow her back were ignored.
So what happened one of the German boys had asked.
The computer fault proved fatal, Alan had said. Zenobia was abandoned barely half a mile from harbour.
The skipper of the dive-boat had interrupted him. An enormous man, he bore an unnerving resemblance to Popeyes rival Bluto, right down to the navy-blue cap. Her crew do nothing, he growls. They just sit at the jetty cafes, drinking ouzo and watching her die. It take two days for her to sink.
Zenobia now lies abandoned and unsalvaged 40m down on the sandy seabed. Arguably one of the most impressive wreck dives in the Mediterranean, an entire industry has been built up around its misfortune, and the embarrassment of its designers.
Our two dives on the Zenobia are the last of a package put together by our dive centre in Paphos. The instructors there had promised us that these were the best dives on which to end our holiday.
Now, as we float past the wrecks midships section, I understand why. Clusters of large grouper swim up to investigate us, but remain just out of reach.
On a good day, Captain Bluto had promised us, you see tuna or barracuda. Maybe today... The tuna and barracuda are conspicuous by their absence during our morning dive, however.
The Swiss emblem is still clearly visible on the Zenobias enormous funnel. It soon becomes clear that the cargo is also largely intact. The vessels first and only consignment of freight included more than 100 articulated lorries, and scores of trucks crowd the ships upper decks.
Some lorries have broken free of their moorings and youll notice that theyve plummeted to the seabed, Alan had told us. The impact smashed their doors open, so keep an eye out for where their cargoes of eggs, paint and air-conditioning units have spilled out.
Its still possible to discern the make of the lorries - Volvos, DAFs and Mercs. But we had been warned to swim well away from them.
The chains that hold them to the deck have really rusted over the past 20 years, Alan explains in his soft Brummie accent. Most of those trucks weigh over 40 tonnes, so the danger should be obvious. If one falls on you, youll have the pleasure of going down with it!
On our afternoon dive, we are briefed to penetrate one of the more accessible parts of the hull. Our entry point is through a gantry towards the stern, and we make our way cautiously into the ships cafeteria. Being inside the wreck for the first time is unnerving. Our world has literally been turned upside-down.
Those of us with underwater torches shine them into the far corners, although their beams barely illuminate the darkness. Isnt that a coffee-machine I can see in the gloom Waterlogged carpet flaps in my face, and I take extra care to avoid the tangle of wires that trail across what used to be the cafeteria ceiling. Underwater obstacles like these can make even the most basic form of wreck penetration hazardous.
Those of you whove never done a wreck dive just need to remember one thing - respect, Alan had said. Theres no such thing as a straightforward wreck dive. Talk to me about getting a wreck speciality if you still feel like it afterwards!
Our team exits through one of the windows in the superstructure above (all Zenobias portholes have been smashed as a safety precaution). Some are clearly panicked by the experience and liable to rush their ascent. One Dutch guy is in such haste that his tank crashes against the window frame and he swims straight into the fins of the diver in front.
I wait until the exit point is clear before ushering Helen upwards. In this confined space, I can understand why some of the divers are in such haste to leave.
Alone, the only sound is the hiss of my breathing. Little sunlight reaches these depths, and the surface seems far away.
Double-checking that none of my equipment is tangled up, I make my way out with some relief. Maybe Ill consider that wreck speciality, I think.
Before flying to Cyprus, we had had reservations about diving in this part of the world. From our research, this part of the Mediterranean had not seemed to be renowned for brilliant diving, and those reservations had been underlined during our first dives.
Yes, it had been interesting to explore the smaller wrecks around Paphos such as the Achilleas and the Vera K, but other than two octopuses and a brilliant red hermit crab spotted on a night dive earlier that week, the lack of marine life variety had disappointed us.
At least there had been none of the overcrowding we had been warned to expect. Today our dive boat is alone on the water, and having the Zenobia to ourselves makes it easier to appreciate its comparatively good condition.
Equally, the ambient conditions mean that youll have no problems with poor viz, Alan had said. Those of you whove dived in the UK will know what I mean! Alan worked in Cyprus for 15 years and vowed never to dive at home again. The British Isles may have more wrecks than any other country on Earth, but thats pretty useless if you can barely see your own hand in front of your mask! he laughs smugly.
We wont be seeing you up at Scapa Flow next summer then I had asked.
We make our way towards the Zenobias uppermost levels. Peering through the upper hull windows, there is little to see beyond twisted metal, as much of the internal partitioning has collapsed. Grouper gather around us as we make our final sweeps.
Then, a few metres further on, visibility clears dramatically. Ahead, the bridge comes into view and everywhere there are sea-bream with their eye-catching zebra stripes.
The prow is like those of ferries that plough across the English Channel, but coming face to face with a ferry at the bottom of the ocean is a haunting experience.
Seaweed is draped over the radar tower and what was once the focsle. Barnacles have begun to soften the harsh steel lines, and year on year, soft coral increases its foothold on the metal.
I reach out to touch a companionway railing swathed in seaweed, icy to the touch. Eventually, marine life will envelop the superstructure entirely. The tragic and beautiful Zenobia is a ghost ship now, but its a haven for sea life.
A deco stop is required and we congregate around the emergency air tank at the 5m-point. Then Helen directs my attention back down towards the hull as a procession of midnight-blue barracuda, each the length of my air cylinder, cruises gracefully past.
Last to emerge from the waves is Alan.Good one he asks cheerily.
Incredible, I reply, although it hit me today why wreck-diving is a speciality.
Alan nods. A couple of years ago, a diver was exploring the lower decks and became trapped. He only survived by finding an old air pocket, which was amazing luck. He still had to wait for two hours before they rescued him, though.
I am glad not to have been told that before the dive. Although there were no fatalities when Zenobia sank, several divers have lost their lives on this site.
Skipper Bluto has other worries. He gathers several tanks in his huge hands for re-filling. Hot, he grumbles, very hot - even for us. In Cyprus, it not rain for four months.
In my country, I say, it hasnt stopped raining for four months.
I gaze out across what Homer called the wine-dark sea, my hair drying in the breeze and the sun on my face, and soak up the atmosphere. The smell of foreign cigarette smoke mingles with sea air, and I can smell couscous being warmed in the galley.
Alan, I say, about that wreck-diving qualification...