Its funny how easy it is to overlook the obvious. I finally twig to this particular bit of obvious on Steve Lewiss boat Blue Shark. We are on our way from Neyland, out through Milford Haven to dive the wreck of the St Jacques, a victim of one of the U-boats that used to lie in wait in the approaches to Milford Haven during World War One.
As with most wrecks in the area, diving the St Jacques is tied to slack water, and were wondering what to do for the second dive. Its the sort of boat journey and discussion I have had countless times in the past.
How about the Thor Done it. The Landing Craft Done it. The Dakotian, the Behar Done them.
Conversation drifts to another usual subject - that it was a shame the authorities hadnt left the Sea Empress for us to dive on after it had spilled all its oil. Steve points out the last pier on the right, where the Sea Empress had been docked while it underwent temporary repairs. He explains that the pier had been built so that the Esso refinery could take supertankers during the 1970s oil crisis, when the Suez Canal was closed.
Then the economics changed, and in 1983 the refinery was decommissioned, dismantled and shipped off somewhere in the Middle East.
What we have left is an enormous, unused pier - about twice the size of any of the other piers in Milford Haven.
I have seen this pier countless times. It hasnt been in general use since 1983. Diving it hasnt even occurred to me before. Does anyone dive it I ask. Whats it like Do we need permission from the Harbourmaster
Steve explains that he has worked on a few zero-visibility commercial jobs below the pier, that as far as he knows no-one dives it as a sport dive, and that there are no restrictions on diving, as long as divers stay out of the shipping channel.
So we put the idea aside, have a good dive on the St Jacques (see this months Wreck Tour), and come back later.

The timing of dives this far into Milford Haven is critical. Further in, the channel narrows, the current gets stronger, the seabed gets siltier and the visibility turns to mud. Visibility is generally better towards the top of an incoming tide, and slack is pretty much on high water.
Everything else may be easier to understand if I describe the shape of the Esso pier. It is a complicated structure, with a straight pier leading 1km from the shore to where a T reaches parallel to the shore for 1.3km. Every now and then the pier widens to platforms for buildings and work areas, the whole lot supported 7 or 8m above high water by thousands of concrete pillars.
The depth on the outside edge is charted as 15-20m. Tankers would dock on the outside of the pier, their cargo pumped ashore through pipes running along the stem of the T.
We dive on the inside edge of the pier, with strict instructions from Steve to make sure we surface inside it, as the outside is the shipping lane. We also dive just after high water, so that the current will carry us away from the pier when we surface. Diving any earlier would have given Steve problems picking us up, with the current pushing the boat under the pier and among its legs.
Starting the dive is the difficult bit. Steve reverses into the inside corner of the T as close as he can. We are beneath the overhanging deck and within a couple of metres of one of the legs, with the current pushing the boat away. The boat in neutral, Steve signals go, we jump in and leg it for the bottom at 15m.
On the stem of the T we dont get much shelter, but working out to the cross of the T we now have the shelter of all the pier legs upcurrent from us. Visibility varies in bursts, from as much as 5m to less than 2m.
The legs are covered in fat-looking plumose anemones, hydroids, tunicates and clumps of mussels, yet none are that strongly attached. Crabs scuttle aside, leaving a trail of detritus cascading downwards. The slightest knock sends a cloud of silt and marine life spreading into the current, and we are forced to find a fresh leg to examine.

Between the legs, the silty seabed is scattered with items that have fallen or been tipped: bits of scaffolding, bottles, cans, chairs - all the usual pier junk.
Yet the thing about piers is that they are truly three-dimensional. When you think about it, although a diver can move in three dimensions, most dive sites are closer to two, so we follow the face of a reef or the deck of a wreck.
Those two dimensions may alter during a dive, as we go over the side of a wreck for example, but at any point in time only two dimensions are relevant.
Among the legs of this pier, on the other hand, we have three dimensions on a big scale. Rather than hugging the silt, we can move up and down in the water, spiral around legs and swoop between them.
Late in the afternoon, little light penetrates the water. Further under the platform, it is virtually pitch black. Moving with the current and along the pier we get away from the platform to where the legs are more widely spaced. They are so far apart that we have to be careful not to lose the pier completely, even in the improved light.
The current is unstable, giving only minor help to navigation. Perhaps I should have been carrying a compass, an item of equipment I use so rarely that most of the time I simply dont bother. But then I look at my buddys compass and realise that with all the metal in the pier, it wouldnt do much good anyway.

Most piers are easy dives, often used for basic training, but I wouldnt classify this one as a dive for beginners. There are too many factors to consider; unstable current, varying visibility, complex navigation, three dimensions and consequent buoyancy control, plus the difficulty of picking up divers if they surface in the wrong place, combine to make this a reasonably advanced dive.
We surface among the pier legs, the only way to be sure that were not on the channel side of the pier. It turns out to be a good move; one leg further out and we would have been. A quick navigation check, then we go back down and across the pier to the inside, where Steve can pick us up.
So how does a pier 1000 times bigger than the usual pier dive measure up Does 1000 times bigger make it 1000 times better I dont think anyone could claim that, but it is certainly worth a dive or two. In a world where divers are setting new records in depth, cave penetration and endurance, I can now claim to have done the UKs - and maybe even the worlds - biggest pier dive!
But there are other discoveries to be made in south-west Wales, and some of them are to be found out of Fishguard.
A good wind is blowing from the south-west, but the sea conditions arent that serious as we head from Fishguard to Strumble Head in a RIB operated by locally based Celtic Diving. We have some protection from the north-facing coast. Round Strumble Head, however, everything changes. We lose the shelter of the shore and enter the area of strongest tides. It is decidedly unpleasant.

Our plan had been to dive the wrecks of the Calburga, a 1406 ton barque that was blown onto the rocks at Penbrush Point in November 1915, and the Vendome, a 418 ton steamship that ran onto Tri Maen-trai in December 1888.
Celtics RIB can handle it, but after a quick inspection of both wreck sites, we decide that we shouldnt be diving here.
Mark turns the boat round and we retreat behind Strumble Head, passing close inshore below the lighthouse and the whale-watching lookout point, though no-one is watching and we dont see any whales. We soon find shelter and flat water by Pen Caer, the next small headland back to the east.
The chart doesnt really have enough detail to allow predictions of what the seabed will be like, so we make a few runs in and out with the echo-sounder. It looks as if a shelving ridge runs out from the point. For lack of anything better to do, we may as well have a dive here. It looks interesting enough on the echo-sounder and, with a current coming round Strumble Head, there should be some marine life.
We descend just into the bay. The seabed is at 15m, scattered rocks leading out from a rocky slope. Just below the kelp line, most of the rocks are covered in a brown turf of bryozoans and hydroids, with the occasional clump of dead mens fingers and patches of small anemones.
Following the ridge out and leaving the shelter of the bay, the current picks up - and so does the marine life. Its the same sort of life, but bigger and fatter and more of it. The balance changes, with large areas of the rocks encrusted with sponges. The patches of anemones grow larger. The bryozoans and hydroids get less space to themselves.
Dogfish resting on the rocks are surprisingly alert, twitching away almost as soon as we notice them, with none of their usual torpid behaviour.
A rock moves and turns out to be an octopus. A lesser octopus, to be more precise. It swims only a few metres before settling and pretending to be a rock again.
The pursuit continues in this vein for a while, but no amount of careful stalking will let me get quite close enough.
Turning back towards the bay and ascending the first ledge, a lobster is standing outside its hole. It isnt that fast to retreat, and is even inquisitive enough to come back out to investigate my buddys finger.
The current has picked up considerably. We had been aiming for slack water on the wrecks, had begun the dive after the calculated slack, and were now ascending into quite a brisk flow. Popping my delayed SMB, I am halfway across the bay before surfacing.
Theres an easy measure of a good dive: I had no trouble finishing a film.
For a second dive we drop in with some seals a bay further back behind Carreg Gybi. There are a fair number on the surface, but none really want to play under water. Its one of those things about seals. Sometimes they do and sometimes they dont.

Next day, we try again for the wrecks, this time launching from Porthgain, about the same distance in the other direction, to the west of Strumble Head. Whether we will be able to dive or not is marginal, but its worth a look. Our journey is more exposed, but we dont have to pass through the standing waves at Strumble.
At the wreck sites, we loiter for an hour or so to see if the waves will drop as the tide turns, but no luck. We could probably dive, but the pick-up would be too close to the rocks for comfort, with waves and wind pushing the boat ashore.
We retreat to the shelter of Abercastle and decide to investigate the headland. Its more of an almost-detached island to the west of the inlet, marked on the map as Ynys Deullyn, though dont ask me to pronounce it.
Its a shallower dive, though pretty much the same dive plan - drop into the sheltered water behind the headland and work our way out into the current.

Much later after slack, the current is considerable. We have to hang on and plot our route between rocks. Deep gullies provide some shelter.
Spider crabs scale the walls, outstretched claws menacing their reflections in my camera port. Wrasse nose up and down, forever curious of new visitors to their range. It isnt long before I find another octopus, cautious but less so than yesterdays example. I stalk it along a gully and over a ridge.
Wary of the waves off the island and the current, I work my way back inside the shelter of the point before surfacing. Another film finished. Another good dive.
The sky is clearing and the sun is finally out, though the wind doesnt seem to be letting up. Back at Porthgain we enjoy ice creams, then a pint on the pubs terrace overlooking the harbour. Its hard to believe that it was so unpleasant out at Strumble Head.
I have some other diving to do in Pembrokeshire, so its a few days before I return to Fishguard and have another try for a wreck. Conditions are perfect and the Vendome turns out to be well worth returning for.
But thats not the point of this story. If conditions had been perfect a few days earlier, we would never have explored what turned out to be a couple of very good scenic dives. For any divers less fixated on wrecks than me, they are easily worthy as destinations on their own merits.

oops, John Liddiard didnt give the strobe time to charge, but this picture on the pier legs seems to have worked anyway
a crab scuttles across a patch of mussels, leaving a trail of debris
This lobster is curious enough to investigate a beckoning finger
a lesser octopus
spider crab
an unfortunately named boring sponge


GETTING THERE: Milford Haven Esso Pier - follow the M4, A40 and A477 to Pembroke Dock, then cross the bridge to Neyland and follow the signs for the marina. Fishguard - follow the M4 and A40 to Fishguard and on to Goodwick (where the ferry terminal is). Celtic Diving is at the top of Main Street on the hill above.
DIVING & AIR: MH - Pembrokeshire Dive Charters 01437 781569. Fishguard - Celtic Diving 01348 874752, www.celticdiving.co.uk.
LAUNCHING : MH - Slips at Neyland and Dale. Fishguard - Public slip by Ocean Lab and the tourist information centre, just along the waterfront from the entrance to the ferry terminal. It dries for a couple of hours either side of low tide. There are also slips at Porthgain and Abercastle, though Abercastle is wet only at high tide.
ACCOMMODATION: MH - Pembrokeshire Dive Charters can arrange accommodation at the Lawrenny Castle hotel in Neyland. Fishguard - B&B at Celtic Diving.
QUALIFICATIONS: The pier dive is not a dive for beginners but Fishguard offers something for everyone.
FURTHER INFORMATION: Admiralty Chart 2878, Approaches to Milford Haven. Admiralty Chart 1973, Cardigan Bay - Southern Part. OS Map 157, St Davids and Haverfordwest Area. Tourist Information, MH 01437 763110, Fishguard 01348 872037.