HOW DEEP IS THAT OLD JAPANESE WRECK called the Katsuragisan Maru, up on the north-east pass of the lagoon, I asked at the Blue Lagoon Dive shop.
Deep, was the reply. Chenney Tipwek, one of Truks most experienced guides, added: Ive told people for many years that katsuragisan means real deep. No one has been there for years.
My friend Pete Mesley, a technical diving instructor from New Zealand, looked at me and said: OK, lets prep the rebreathers. We leave at 8am tomorrow.
Truk Lagoon, in Chuuk in Micronesia, is, quite simply, the worlds premier wreck-diving location (Deep Wrecks, December 2008 and Ghost Ships, March 2009).
I had returned specifically to explore the most rarely dived wrecks, and Katsuragisan Maru was one of them.
Every morning is beautiful here, and the following morning, as we headed out to the north-east pass, was no different.
Because Blue Lagoon Dive Centre is located on the island of Moen, the north-east pass is the quickest to reach of any shipping entrance within Truk Lagoon. Despite this, divers rarely venture out to the pass because the Katsuragisan Maru is the only wreck in that entire deepwater patch, and most visiting divers are there for the shallow tourist sites. It is also the deepest wreck in the lagoon, at around 70m.
Another experienced guide from the dive centre joined us, local man David Fuiti. He knew where the wreck was, and had dived it years ago, on air! Naturally, he couldnt remember much about it.
One thing we have learnt in Truk is to respect the guides, and their impressive method of locating the wrecks! With few if any transits a distance from the islands, and certainly no modern technology, they stand on the front of the boat staring into the ocean and shouting directions in Trukese to their boat-driver. One can only sit back, enjoy the local bananas and be impressed.

ON SOME DAYS, David would find the wreck; on others, he struggled.
We gave him time until he looked really fed up, then we would pull a GPS and bottom-sounder from the rucksack. As skilled as they are at Blue Lagoon, and as knowledgeable of every wreck, everyone has an off-day.
As a heated conversation in Trukese usually follows, one cant help thinking that pride has been dented in a small way by modern gizmos!
David and our usual guide, Nick Missauo, donned single 12-litre cylinders and leapt overboard, pulling their masks over their faces a thousandth of a second before hitting the water! Dont you just hate people who dive for a living
We pre-breathed our Evolution rebreathers, and made last-minute adjustments before dozing in the morning sunshine.
The silence was broken a short while later as David surfaced, took his regulator out of his mouth and called out: The wreck is down there!
He had found it at the first attempt, with what can only be described as very distant transits, lodged somewhere in the back of his memory - impressive.
Pete Mesley had advised us jokingly to bring a stick to fight off sharks on decompression. Ive heard they love the deep water away from the islands, especially out here! he had said.
He wasnt wrong. As soon as we dropped over the side, you could see sharks circling below at depth. A handful of blue fin-tips wouldnt put us off, however. We were buzzing with excitement to visit this rarely seen wreck.
Blessed with awesome visibility, the wreck soon became apparent on the descent. Davids anchor had hooked into it amidships, slightly aft of the still-standing smokestack.
At depth, my PO2 automatically adjusted to 1.2. The next 45 minutes was mine to explore a new wreck.
First to strike me were the incredible number of navigational lanterns lying around the site. I reckon I have explored some 400 virgin wrecks over the past
two decades, but had never seen so many different lamps on one wreck.
Aft of the bridge, and on the upper deck level before dropping down to the aft well deck, I saw a bunch of fairly large lamps that had clearly been gathered up by a Japanese sailor before the ship sank.
Marine growth over more than 50 years had moulded them together.
The wreck appeared to be sitting on an even keel, bow facing west.
A wonderfully carved sand-dune seabed left it in a slight scour a fraction deeper than 70m. There was, however, little point in dropping to this depth, because most of what was to be seen was on the decks and within the four holds at around 65m.
I swam to the bow tip with my good friend John Dryden, and slowly explored the decks as we returned to the anchor-line. Visibility remained crystal, so it
was easy to see the sharks sleeping on the decks in advance, allowing us to
give them a slightly wide berth!
Lanterns apart, the other point of interest on this first dive was the way in which the wreck was collapsing. On the bow, the surrounding hull-plates were peeling away like the lid of a sardine-tin.
Divers often notice that sections of hull are missing, and large hull-plates lying on the seabed, but here it was as if we had disturbed someone in the process of peeling them off!
We finished our dive around the bridge area, inspecting navigational equipment that was lying there - but, of course, we wanted more.
Katsuragisan Maru (maru means merchant in Japanese) was a classic tramp steamship of about 2500 tons, built in 1925 by Mitsui Bussan Kaissha Co in Tokyo. The Japanese used the ship as a naval miscellaneous auxiliary vessel, transporting military personnel and supplies during the war effort.
Her sinking was a case of lack of communication between the Japanese forces. Most of the ships in the lagoon were sunk by US aircraft during Operation Hailstone, but a mine ended this ones career a few months earlier.

AT 5.30 AM ON 7 JANUARY, 1944, the vessel entered the north-east channel, loaded with war materials. The pass had served as a primary shipping channel before the war, and then had been heavily mined to destroy any enemy submarine or invasion craft attempting to enter the lagoon. Katsuragisan Maru sank about half a mile into the pass, with five of the 41 crewmen killed.
The Japanese concluded from the incident that escort vessels were not being sufficiently informed about the status of areas restricted to navigation.
The Japanese base commander decreed that all new captains, masters and those navigating the area for the first time should be kept in the picture using updated charts and materials.
Allied intelligence learned of the loss of the Katsuragisan Maru from intercepted messages, and would have used this information should the Allies have sent their own vessels deep into the lagoon for the attack.
The Katsuragisan Maru wreck was discovered by a Canadian team of film producers in 1994, after a search using sophisticated underwater detection equipment. They dived and filmed it for a documentary about the legacy of Truk Lagoon exactly 50 years after the sinking. It has hardly been dived since.
We were the first CCR divers to visit, and with the benefit of extended bottom dives hoped to piece together a better story of this wreck as it is today.
We would also be interested to find out exactly what the vessel had been carrying deep inside her holds.
The upright bow is the highest section of the wreck. You can access the interior via a doorway on the well deck, or through gaps now evident in the hull.
The upper forecastle deck level is covered in typical Truk marine coral, with shoals of fish present as well as the resident sharks. A single windlass, adorned with hard corals, sponges and featherstars, is mounted here. Over to the port side lies a large cable-spool.
From the well deck on this side, an open door leads into what can only be described as a washroom. We saw toilets, but also the unusual sight of a tiny bathtub. Why would a childs bathtub be on the ship
Immediately outside the door, we dropped through the deck into no 1 hold to see those iconic Japanese gas-masks and canisters. There seemed to be more here than on all the other wrecks in the lagoon put together.
This cargo was an impressive sight, especially with the canvas material well-preserved. The hold also contains boxes of what look like the Japanese equivalent of dynamite sticks!
From above, the hold appears full, with no way in for divers, but it is an extended hold that runs under the forecastle with an adjourning bulkhead, and can be accessed via a collapse in the forward starboard side deck.
The remainder of hold no 1 is full of rolled-up steel-mesh matting which, we believe, was to be used in constructing an airfield on the island of Eten. A single hatch-cover beam remains in place, and the ships mast has fallen completely across the hold.
Moving towards amidships, we immediately came across hold no 2. This at first appeared to be empty, but on investigation proved to contain a varied cargo of electrical equipment and rolls of hawser cable, deep within its recesses.
There were various wheels for obscure applications, and a mountain of bottles of the sort carried on just about every Japanese ship sunk in Truk Lagoon.
The amidships island superstructure is a scene of chaos. After the ship struck the mine, a serious fire raged through the bridge, destroying the entire
wooden superstructure and weakening the steel beams. It looks as if the wreck has imploded.
Here its possible to see the exposed reciprocating triple-expansion steam engines that provided some 181hp to a single screw. Because of the collapse, all sorts of artefacts can be seen here, from navigational equipment like the helm steering position to portholes, wonderfully decorated Japanese porcelain and even more lanterns.

THE FUNNEL STILL STANDS, and aft of this on the starboard side more china pieces can be seen, including cups, plates, saucers and sashimi dishes. Several pieces carry the flag symbol of the owner, Mitsui Bussan Kaisha.
More fish hang out around the amidships island of the wreck, dominated by large numbers of schooling yellow grunts along with surgeonfish and resident nurse sharks that are quite a few feet long.
Some interesting equipment lies near the aft end of the boat-deck, with what looks like a radio rack with wires and cables strewn all over. Below this area are compartments once used to store smaller cargo and crew essentials.
Small lanterns mingle with other items, and two more lie in the open area of the starboard deck just forward of no 3 hold. This hold too is full of rolls of wire-mesh matting.
The broken aft mast lies diagonally across the hold and over the hatch-cover beams, its triangular crosstree on the port deck. Looking over the starboard side of the wreck at this point, you can see the damage caused by the mine.
Just before the stern we saw several vehicles stowed in the final hold, with three trucks lying beside each other in line with the vessel. One, clearly an officers car, was beautifully decorated in red and green corals and made for excellent photography with the deep blue Pacific backdrop.
An intact ladder leads to the upper stern deck, and a spare anchor is lashed to the rear deckhouse on the starboard side. The stern section of the wreck stands lower than the bow, and appears to be very exposed to the ocean.
Marine growth completely covers a large gun and mount platform, the gun-barrel pointing slightly to port.
What appears to be a depth charge is fixed to its racking on the port side, and a large steel cable drum is similarly attached on the starboard side.
You wont find the Katsuragisan Maru on normal tourist route listings, and advanced diver training is required to explore this wreck using trimix. Blue Lagoon can provide mixed gas, in association with Pete Mesleys Truk Lagoon expeditions. It also knows where the wreck is, along with many other rarely dived and deeper sites.
Its location is now etched in the guides impressive memories - not to mention Mesleys GPS!

For further information about diving Katsuragisan Maru and other wrecks, or joining expeditions to Truk Lagoon, visit www. petemesley.com and www.truk-lagoon-dive.com