Kyokuzan Maru

The descent follows the rigging down from the masthead to the deck, and from there the ship runs the length of the dive. She sits upright and close to whole, and nobody gets round her in one dive.

The forecastle at the bow opens straight into rooms with things left in them. Behind it are three holds on two levels: 200 litre drums and unrecognisable freight on the 'tween decks, and the vehicles below. A Japanese Army jeep chassis sits in the second hold from the stern, largely intact. Staff cars and trucks are in the others, one of them now identifiable mainly by its whitewall tyres, which seem impervious to seawater.

The engine room offers options. A coal bunker in the third hold opens into it, and so do the bridge area, the skylights and the large hole where the funnel used to stand. A fifth way in runs from outside the hull through the prop tunnel. The engine itself was salvaged, but the boilers are still there, and divers describe dropping a little deeper down their sides and flying from catwalk to catwalk.

The bridge is a dive of its own: cabins to work through, a large bath on the port side, kitchen fittings, and a floor of broken plates in what was a canteen. You can stand up in the wheelhouse. The funnel lies over to starboard almost horizontally, and it is an open swim-through.

Batfish are what divers talk about afterwards. They are big and curious, and one group found that mimicking the grunts the fish make to each other pulled them in until one was studying them through the mask from a few inches away. Keep still and breathe gently and they stay.

The contents are the rest of it. Inside are things people used: a bath, kitchen fittings, crockery stamped with the ship's insignia, staff cars and trucks with their tyres still on. The hull is upright, the funnel is a swim-through, and a day spent on two dives is the standard way to see it.

She was an Imperial Japanese Army cargo ship. In September 1944, after American carrier aircraft struck Manila Bay, the Japanese dispersed their auxiliary shipping into the Calamianes. She anchored in a small harbour on the north coast of Busuanga with two other cargo ships.

On 24 September a squadron of dive bombers flew 332 miles from the American carrier force to reach them. Twelve took off and ten arrived. They found the three ships almost line abreast and reported a bomb hit on the port side of the single-stack ship, three or more very near misses, and a fire burning topside near the middle of her. She is the only one of the three on the bottom today.

After the war her engine was cut out and the prop shaft was removed with explosives, so some of the damage a diver sees dates from salvage.

Stay off the floor of the lower holds. A low white mist lies in the bottom of one of them, thick enough that a diver in the 1990s gave up trying to examine the hold. It has been called asbestos dust and is unconfirmed, and the instruction is the same either way: do not sink into the layer, do not fin through it, do not stir it.

The holds and the engine room are the dive here, and the vehicles are deep enough that divers come off this site with lengthy decompression stops. Plan the gas before you drop, and ask about Nitrox when you book. Hover past the handrails, because a tasselled scorpionfish sits along them.

Help is a long way off. The wreck is a boat ride and an hour of road from Coron Town, and no working recompression chamber is confirmed in Coron. Your cover should pay for chamber treatment and the transport to reach it, the boat needs oxygen aboard, and the operator should be able to say where the chamber question stands on the day you dive.