I glanced at my buddy Jane, who signalled OK. Suddenly, like a scene from a nightmare, the head of a large conger eel rushed towards me and snapped at my mask. Janes eyes widened in surprise. I grinned, gently pushing the rather confused eel away before giving a reassuring OK in return. Then there were more eels, at least six, coming at us from all angles. Jane, still wide-eyed with fright, looked at me with a what now expression.

Handing her a piece of fish, I waved my hands around as if to say lets play! Before I could reassure her that she had nothing to be afraid of, she disappeared from view as three of them homed in on the fish in her hand.

This was my second dive here and, in the same way as Jane was about to, I had already experienced a change in my attitude towards congers. Despite being the subject of so many tall diving tales, they are surprisingly gentle and far from being demonic creatures from the deep - as some people maintain.

We were diving Rathlin Island, located seven miles north of the coastal town of Ballycastle in Northern Ireland. A mere giants stone throw away from the famous Causeway, Rathlin is already well-known for its picturesque ruggedness, its wildlife and its long and bloody history. More recently, as a result of being a natural disaster zone for shipping, the areas clear, rich waters and spectacular underwater cliffs are becoming increasingly popular with divers.

These congers were my introduction to underwater Rathlin. It had been explained that they were gentle and, with this in mind, I was looking forward to meeting them. On entering the water, however, my confidence was shaken by the sight of three divers from Dublin struggling with a huge eel that had swum up the line to meet them, intent on devouring a goody bag full of fresh fish.

Amid the confusion, my buddy Jamie attempted to tug the bag from the congers grip, but the eel twisted the bag into a knot before swallowing it and retreating to the safety of the wreck - and possibly a bad case of indigestion. After that I became very conscious of keeping my fingers firmly in fists - lest they get dragged off by another hungry eel.

However, 5 minutes into the dive I had forgotten the incident and was fascinated by the slow and gentle movements of these fish. They are so placid that it is possible to stroke them and manoeuvre them around without being bitten.

Congers are believed to live for a maximum of 15 years before migrating to deep water off the Azores, where they spawn and die. However, one monster eel, identifiable by its characteristic markings, has been a familiar sight around Rathlin for about 20 years. Eels are more numerous and active during the summer months; only the larger ones stay around during the winter. One of the most intriguing things about congers is that they are almost completely blind. Being primarily nocturnal, they hunt by scent. Their large eyes are almost useless, and they are unable to recognise anything in front of them until it is actually on their nose. Move a piece of fresh fish too quickly aside, and the conger will miss it completely, swimming off in a straight line, looking slightly confused at having lost the scent trail. What little vision they have got shows in their habit of tasting anything white or bright yellow - fingers, masks, regulators and cameras were all nibbled, albeit gently.

After this adrenalin-filled first day, I wondered whether the rest of my weeks diving might be an anticlimax. Not a bit of it!

The next day we dived the north wall of the island. A spectacular freefall to 50m down a cliff covered in anemones, dead mens fingers and a variety of large crayfish and lobsters. Slowly ascending up the wall, we drifted gently along at 20m, where we could clearly see the surface and watch a shoal of mackerel speed back and forth. Our group decided it was such an interesting dive, that we elected to dive it several times over the course of the week.

Another good dive was the wreck of the Lochgarry, a 1670 ton passenger-cum-troop ship that sank in 1942 with the loss of 29 lives. She rests upright in 34m of water, complete apart from a damaged bow. Exposed to a strong current, she is diveable on the slack. The visibility is very good indeed. Being used to the murky waters of the South of England, I couldnt believe I was at a depth of over 30m. Shoals of pollack added to the picturesque views across the deck and a pair of ling hung mysteriously under the keel, melting away like ghosts on our approach. An octopus, momentarily caught out in the open, got a chance to show off its acceleration.

We avoided accumulating too much decompression on this wreck. In addition to the current, flagpoling on the line was made even more unpleasant by a bombardment of stinging lionsmane jellyfish. All of us sustained stings to our faces and hands which required liberal doses of vinegar once back in the boat.

Within Church Bay itself lies the wreck of HMS Drake - one of the most dived wrecks off the Ulster Coast. Once a 14,100 ton heavy armoured cruiser, she was sunk in 1917 after being hit by a torpedo, and came to rest protruding above the water in the bay.

The Drake is diveable in most conditions. There is a lot of life including lobsters, edible crabs and angler fish. It is also a recommended night dive. Until 1979 she contained much live ammunition, but the Navy removed all the cordite and carried out a thorough explosives job. As a result she is now reduced to a rather flat tangle of metal, although the guns are still clearly visible. A trawler is wrecked alongside her but is indistinguishable from the main wreckage. Despite the apparent carnage, there were three divers busy extracting brass knick knacks from inside her during our stay.

Indeed many of the local wrecks have plenty of shiny stuff. One wreck which still contains many goodies is the Santa Maria - one for very experienced divers only. I opted out, not having built up my dive fitness and confidence to spend time at depths in excess of 48m. I left it to other divers from our club, and listened with envy to their accounts of the dive.

Another exciting dive is Shamrock Pinnacles, located about 4 miles north-west of the island. Here, the water is very clear and the life is outstanding. Care must be taken though, since the top of the rather flat pinnacles starts at 25m and the currents can be quite fierce.

There are countless dive sites around Rathlin and, as well as the deeper walls and wrecks, our group enjoyed some fine shallow drift dives. A particularly memorable one was near Bruces Cave, where Robert the Bruce is reputed to have watched a spider try, try again before leaving the island to become King of Scotland.

Most of the diving on Rathlin is for more experienced divers, although the tame congers and the Drake are ideal for a novice with a few dives under his belt. There are fierce up and down currents on the north of the island that can catch out the unwary. It is better to dive it with the guidance of an experienced skipper.

At the moment Rathlin is undeveloped. There is a pub in front of the harbour. The shop and post office are extensions of peoples homes. Electricity is provided mainly by wind generators with petrol generators providing a backup. It is peaceful, despite the influx of day trippers on the footpassenger ferry. Divers are welcome and the people are friendly, making for a totally stress free atmosphere.

There are none of the drawbacks associated with some of the busier dive sites. Where else could you leave your computer on the dockside overnight and find it in the same place in the morning

Plans have been hatched to try to persuade the Department of the Environment to designate Rathlin a marine reserve. With its proximity to the mainland, Rathlins popularity among divers could be about to soar.

  • Simon Williams dived with Tommy Cecils Rathlin Dive Centre. Ferries run from Stranraer to Belfast and discounts are available through Rathlin Dive Centre. Cars cannot be taken onto Rathlin Island. The island ferry runs at regular intervals from Ballycastle to Church Bay, costing£5.60 return per head.
  • Full-board accommodation with two dives costs 40 per day, including tanks, air and weights. Diving is from an 8m, 250hp inboard RIB. Additional dives cost£10.
  • Rathlin Dive Centre, Rathlin Island, Ballycastle, Co. Antrim, N. Ireland BT54 6RT (tel./fax. 01265-763915).